The Checker Murders is a 16,000 word novelette published in seven monthly installments. It is perhaps the most extensive work of checker fiction ever published. We hope you enjoy it, but if you wish you can skip to the end to see this week's checker problem. Be forewarned that the problems in this series are for the most part very difficult.

---

A little while later, Sheila made up a bed for Mortimer on the living room couch. "You sleep here," she said. "I don't want to take things too fast."

Mortimer, still floating in a dazzled state, didn't object.

"In the morning we're going to have to figure out what to do. It's Thursday now, and I know neither of us have class until Monday. It's also my day off work. We'll have a little time to work this through."

She paused at the doorway to her bedroom. "Good night, Mortimer." The door closed behind her.

It was already four AM. Mortimer didn't think he'd be able to sleep, but somehow he did. When he awoke, it was bright daylight and he smelled coffee brewing in the apartment's kitchen.

Sheila was up and about, dressed in a snug-looking blue bathrobe, her hair slightly in disarray. She smiled in Mortimer's direction.

"Good morning, sleepy boy," she said in a bright tone. "It's nine AM and time for you to be up and about. As I said last night--- I guess it was actually this morning--- we'd better make some plans here. Things are already happening."

"Uh... what kinds of things?" Mortimer managed to ask, still a bit groggy but coming back to the realization that he really was in a difficult situation and that it wasn't all a dream.

In fact, there were parts of this adventure that he was glad weren't a dream, like just about everything to do with Sheila. But the rest of it ... he wished he could pick and choose. But reality didn't work that way.

"Special Agent Purdy has already called me twice," Sheila was saying. "Once to say that you weren't at home, and then about an hour later to ask if I was sure I didn't have any idea where you were. Now, as I also said earlier, he's not going to come in here looking, but he may have someone keep an eye on the apartment entrance just in case you show up. But since you're already here ..."

"You said he hasn't really got anything on me, though," Mortimer protested, "so why all the drama?"

"He still thinks you know too much about the case, things that you wouldn't have known if you weren't involved somehow. And no, it won't stand up, but you could be in for a few unpleasant days and some legal bills that you probably can't afford."

"So what do we do?" Mortimer asked.

"Uh, you're the one that calls himself Sherlock, so I was hoping you had some ideas. The only one I have is for you to lay low for a couple of days, maybe even a week. But there's a problem with that, too. If you suddenly disappear, you give Purdy more to work with and a better argument in front of a judge for getting a warrant out on you."

Mortimer thought for a moment; at least, he gave the impression of doing so. "Then there's only one way," he said, with all the decisiveness he could muster prior to his first cup of coffee. "We have to go stake out the Glasgow Circle address ourselves."

Sheila stopped in mid-motion, nearly spilling the pot of coffee. "Uh, Mortimer, maybe we should talk about this a little?"

# # #

Over coffee and toast, they discussed Mortimer's suggestion.

"Mortimer, do you have any idea what you're suggesting?" Sheila asked.

"Can't you see, there's just nothing else to be done," Mortimer said. "We know for sure where the next murder will be and I might know how it will be done."

"How?"

"Something to do with black widow spiders. The Black Widow variant of the Glasgow."

"Spare me the technical details," Sheila replied. "It makes sense and I finally understand it, though you don't need to try to make a checker player out of me. But trying to apprehend a dangerous criminal ... isn't that a little out of your range? You're a nice guy and you know how much I like you, but you're not exactly the action type, if you know what I mean."

Mortimer didn't know how much Sheila liked him, but he was beginning to have some serious hopes in that direction. After the way she kissed him last night, and how she was trying to keep him safe ...

"Look, Sheila, you said yourself that we can't go back to the police or FBI. But the murderer is going to strike. We can't just let that happen, can we?"

"Well ... no ..."

"Then it really is up to us, Sheila. We have to prevent the next killing and maybe bring in the suspect. I have a list of names, it's down to three possibilities. Maybe we could narrow it even further with a couple of phone calls."

"Uh ... call the potential killer and start asking questions?"

Mortimer was fidgeting in his seat. "Well, maybe that might not work so well ..."

"Yeah, maybe not, Sherlock."

"OK, but look, we can wait until dark and then take your car over to Aurora. We can be there in fifteen minutes. Even if someone is watching the place, seeing you drive off in the evening will seem very natural, won't it?"

"With you in the car?"

"I'll duck down in the back seat or something."

Sheila laughed. "Oh, Mortimer, you watch too much television. But I suppose it could work, and yes, we can't stand by and let another murder take place. But what do we do if we're there and something actually happens? We can't take on an armed killer. I don't have a weapon and I'm just about certain you don't."

"No, no, I don't like guns." Mortimer gave an involuntary shudder. "I don't even go hunting. Or fishing for that matter."

"Or hiking or skiing, I suppose," Sheila added. "You've got to give that computer of yours a rest sometimes."

They made their plans. They would drive to Aurora in the late afternoon, planning to arrive just before dark. That would give them time to have a look at the projected crime site and find a place of concealment. Then they would wait it out. They agreed that if they saw anything out of the ordinary, they would make an anonymous 911 call. They wouldn't risk taking action on their own. Mortimer argued that they might have to do something, but he privately wondered if it was just bravado. Sheila's comment about him not being a man of action stung a little but he knew it was true.

The only real risk was that the police or FBI might still be watching the Aurora address. But Sheila figured they wouldn't do that; they had surely thrown out all of Mortimer's theory by now.

Sheila went out around noon to get some takeout Chinese for lunch, after having made a crack about that being the kind of food that she understood nerds and hackers to like. She ended up apologizing and offering to buy, and to his delight the whole episode earned Mortimer another kiss.

Sheila returned with the food and a report that there was indeed an unmarked car down the block, in a location with an unobstructed view of the apartment block's entry. "Not good," she said, "Purdy's definitely suspicious of me. That car must have been out there for hours, which means he's got at least a small team on it. You really will have to lay flat on the floor in the back of the car. Or else ride in the trunk." She punched Mortimer playfully on the shoulder.

"I'll go with the floor," he said.

"At least I wasn't followed," Sheila said. "I'm pretty sure of that. So you won't have to stay in back for too terribly long."

# # #

Just before dusk, they piled into Sheila's car, an old four door Chevy, a little more downscale than Mortimer had expected. "Yeah, I know it isn't much, but remember, I have about as much money as you do," she said.

Then Mortimer took up a position on the floor in the back of the car. Sheila told him to stay down and lay as flat as possible until she gave the word. He was to pull a blanket over himself just in case anyone got too close and looked in.

At just about four PM, Sheila pulled out of her apartment building's garage. Sure enough, the unmarked car was still down the street. Someone else was in it, but she pretended not to notice as she drove by. It didn't follow her, and she spent the next twenty minutes or so driving around more or less aimlessly, making turns at random and watching to make sure she was not being followed by any other unit.

When she was satisfied, she made a few more turns and headed toward Aurora by an indirect route. She called to Mortimer, "All clear now, Sherlock! You can get up."

Mortimer shook off the blanket that covered him and groaned. "That took forever, and I'm so sore!" he complained.

"No griping!" Sheila said. "I've got us on our way, what more do you want?"

"I want to sit in front!" Mortimer whined.

"Oh, for heaven's sake," Sheila said, feigning disgust. "We'll be there in fifteen minutes. You can last that long."

# # #

It all worked out about as expected, at least initially. They arrived at their destination in Aurora a little before dark and were easily able to find the address that Mortimer indicated. They parked a few blocks away, intending to walk to their destination.

Mortimer said something about maybe picking up a few snacks first. "You know, like some potato chips and beef jerky," he told Sheila.

Sheila nixed the idea. "Mortimer, this isn't one of your play adventures. You've been at one of the crime scenes. This is all too real."

Mortimer, suitably chastened, shuddered a little.

They walked together until they were within a block of the target address. "Let's split up," Sheila said. "We'll circle the block in opposite directions, then meet up here and compare notes. I don't want the neighbors to suspect anything, and if we're seen walking back and forth several times, someone might notice. We don't need the police being called right now."

Mortimer realized that somehow the lead had shifted to Sheila. It might have been his idea, but it was quite clear who was running the show. Well, he thought, she works in a crime lab and knows more about this stuff than I do.

But Mortimer still felt a little bit of a nagging need to show her he wasn't just a wimpy nerd. He vowed to himself that before this operation was over, he'd do just that.

# # #

About twenty minutes later, they met back at the same intersection a block from the house. They had both had an opportunity to make some observations from both front, back, and sides. Neither of them had seen anything remarkable. The house was a typical split level, with a front entrance, garage with a side door, and a patio entrance in the back. It didn't look as if anyone was home at the moment. They hadn't been able to find much information about who lived there; there was no phone listing and internet searches hadn't shown much.

There was a side street with a vacant lot opposite the target house, and they decided that if they parked by the lot and sat in the car, they could safely observe the house. There was almost no pedestrian traffic in the neighborhood, it would soon be dark, and they felt they had good chances of avoiding detection.

They went and got the car. It was dark when they parked alongside the vacant property. Sheila stayed behind the wheel and Mortimer was in the passenger seat.

"Sherlock, where's your night vision goggles?" Sheila said, obviously teasing.

"Left them at home," Mortimer replied in a matter of fact tone.

"I'm not surprised you have them," Sheila said.

Mortimer grinned. "Gotcha! You just assumed again... although to tell the truth, I wanted a pair but they were just too expensive."

Sheila smiled back, and time passed in periods of silence broken by an occasional remark.

"We're whispering," Mortimer noted, "even though there's no one to hear us."

"Look!" Sheila pointed to the house. A car had pulled up in the driveway. The garage door opened. the car went in and the door closed behind it. Not long afterward, lights started to go on in the house.

"It looks like the owner's come home from work," Sheila observed. "About eight PM; that's fairly late."

Ten minutes later, Mortimer thought he saw movement in the hedges in front of the house.

"Did you see that?" he whispered.

"Yes," Sheila whispered back. "It looks like just that one hedge moved."

They both gasped as they saw a darkly-clothed figure emerge from behind the thick hedge. The hedge was positioned toward the right edge of the house. It seemed to be right below an unlit window. The dark figure pulled himself up by grasping the window ledge. The figure was holding something in one hand, tracing it around the edge of the window.

"He's cutting through the screen," Sheila said. "He's going to break in!"

They watched as the figure dropped the cut screen and the cutting tool to the ground, and instead wielded a short pry bar. It didn't take long to jimmy the window open, and it was done without making any sound that they could hear.

"He's a professional, all right," Sheila said. "I'm going over there to see what's going on."

"Isn't that uh... dangerous?" Mortimer asked.

"I'm trained, and I won't take any chances. You call 911 right away." She was out of the car before Mortimer could say another word.

Mortimer wondered about just how well trained Sheila might be. He didn't think it was usual for law enforcement to take on a possibly armed intruder without backup. And Sheila didn't even have a weapon of her own. You would have thought she might have called 911 /before/ leaving the car.

He watched as she carefully crossed the street, staying low and using shadows for cover. She stopped at the edge of the property and crouched behind a tree.

The intruder had gone into the house.

Time for a 911 call for sure, Mortimer thought. He reached for his cell phone.

Which wasn't there.

Too late, he remembered leaving it on the couch in Sheila's apartment. And of course, Sheila had taken her own phone with her.

No way to make the emergency call unless he too crossed the street and got Sheila's phone.

He realized that if the intruder confronted him he wouldn't have the slightest idea what to do and would probably wet his pants. But he felt the need to act.

Sheila had now moved to the hedges in front of the house. Was she going to follow the intruder inside?

Mortimer got out of the car and started for the street. He was about to cross when he heard a loud scream coming from inside the house. It sounded like a male voice.

Sheila, hearing the scream, quickly pulled herself up by the window ledge and entered by the same route as the intruder.

What was she going to do besides get herself hurt?

Mortimer was across the street and on his way to the hedges when he heard Sheila scream in turn.

There was only one thing to do.

Mortimer felt his whole body start to shiver and shake with fear, but this was the moment for proving himself. No matter how afraid he was, he would have to go in there after Sheila.

He had even less idea what he was going to do than he thought Sheila did.

His real hope was that someone in a neighboring house heard the screams and would call the police. But the houses were set pretty far apart and he couldn't count on that.

He got over to the hedges. No further sound was coming from the house, not that he could hear at this distance. He grasped the window ledge and attempted to pull himself up.

In high school, Mortimer wasn't much of an athlete, and in college he didn't even try. He especially was bad at doing chin-ups. He was having a real time of it trying to pull himself up to the window so he could climb in. The feat seemed beyond his abilities.

How did Sheila do it so easily? he wondered. She was up and through the window in seconds. So was the intruder for that matter.

Mortimer was starting to sweat. Finally he got the idea of pushing against the side of the house with his feet, rather than trying to just use his arms to lift himself. If only he didn't fall and make a racket...

He made it. He was up to the window and starting to wriggle through. That too was a lot harder than he had expected. His legs dangling in the air, he got his upper body through and levered forward with his elbows. He finally fell through and landed in a heap--- in a bathtub.

Luckily, he wasn't very heavy and didn't make a lot of noise on impact.

He heard muffled voices coming from the direction of what was probably the kitchen. The bathroom door was half open.

"There's really no difference if I kill one person or two," a man's voice was saying. "I make my point either way."

"There's no need to kill anyone." That was Sheila. Her voice was unsteady and fearful. "It's not too late to stop. You can get help."

"Lady, if I get caught, I'm going to jail and we both know it. I need to make this clean. Tough luck for you but you shouldn't have interfered."

Mortimer heard a second man. "I didn't do anything to you," the man was saying. "There's no need to kill me."

"This isn't about you," the intruder said. "But you wouldn't understand."

Mortimer realized there wasn't much time left. He had to act /now/. But what should he do?

Was there anything in the bathroom he could use as a weapon? He glanced around quickly; just enough light was coming in through the door for him to make out various objects. All he saw was the usual stuff: bars of soap, a toothbrush, bottles of shampoo.

A straight razor.

The guy who lived here must like close shaves.

Mortimer grabbed the razor and opened it, holding the blade out in front of him. He could only hope that the intruder didn't have a gun, though Mortimer didn't know how else he was keeping both Sheila and the homeowner at bay.

Mortimer moved stealthily out of the bathroom, in a crouch, with the razor held at the ready, although ready for what was something he didn't exactly know. He went in the direction of the voices. Sure enough, they were coming from the kitchen.

Surprise: that was the only thing he had going for him. He would have make his move quickly.

He was almost to the entry to the kitchen. Gathering his courage about him, he made what he hoped was a horrifying facial expression and leaped through the doorway, screaming at the top of his lungs. "Banzai! Stop thief! Single-edged razor!"

Sheila and the homeowner were sitting in a corner of the kitchen, against some cabinets. A stocky-looking man was about six or seven feet away. With his right hand, he was pointing an automatic pistol in their direction.

At Mortimer's screaming entrance, he started to turn in Mortimer's direction. Mortimer was about three feet away and had stopped dead, waving the razor blade around in the air and continuing to scream. "You're under arrest! I have a razor blade! FBI! Drop your weapon!"

The gunman was now facing Mortimer. "Who or what are YOU?" he said, almost laughing.

There was a sudden blur of motion from behind the intruder. Sheila had sprung up from her seated position on the floor and with a spinning motion delivered a hard kick to the intruder's head with her left leg. The man staggered backwards, almost falling into Mortimer, who shrieked and leaped backwards. Sheila's right leg came around and her foot caught the intruder full in the stomach. He groaned and fell to the floor. Sheila was instantly on top of him and the edge of her right hand chopped at the back of the man's neck.

It was all over.

Mortimer stood open-mouthed, the razor still in his hand.

Sheila looked over at him. "Mortimer, you were very brave, but please put that thing down before you hurt yourself."

Mortimer obediently set the razor blade on the kitchen counter, next to a checkerboard that had already been set up to exactly the position he would have expected. The checkerboard was right next to a small metal box. Mortimer didn't have to look to know that the box was filled with black widow spiders.

[black widow spiders]

# # #

The police and FBI were on the scene and had the intruder in custody. Mortimer and Sheila had a long night ahead of them. They'd have to go to the police station and make statements, and that would include some explaining about why they were where they were that evening. But Sheila assured him that it would all work out. The Checker Murders killer had been caught and that was what the authorities really wanted. Sheila and Mortimer had prevented another murder. They wouldn't really be in any kind of trouble.

It was something like five in the morning when their statements were complete and a police cruiser dropped them back at their car.

On the way back, with Sheila driving, they talked about the night's events a little more.

"I had no idea you had combat training," Mortimer said.

"Not exactly combat training," Sheila replied. "But I do have a black belt in Taekwondo. I always knew it would come in handy some time."

"No kidding. That guy probably would have killed all of us if you hadn't taken him out like that."

"I was only able to do it because of you," Sheila said, reaching over to pat his arm. "You really were very brave, in your own unique sort of way. You could have been shot right on the spot. Would you have really used that razor?"

"I don't know," Mortimer said, "I didn't really think that far ahead."

Sheila laughed. "I didn't think so," she said, and they continued to drive on into the night.

# # #

It was starting to become light when they pulled in at Sheila's apartment. Mortimer said he could take a taxi home, but Sheila insisted that he sleep a while first. Mortimer assented readily; he was too tired to object. He started to make up a bed on the couch as he had done the night before.

He felt a touch on his shoulder. "No, Mortimer," a voice whispered in his ear. "Not there."

# # #

They were having breakfast at about four PM. Mortimer had spent an hour or so on the internet, ending with an exclaimed, "Aha!"

"What is it?" Sheila asked.

"The last piece of the puzzle," Mortimer said with satisfaction. "The motive for all of this, and why the killer wasn't any of the three people on my list."

Sheila placed two mugs of coffee on the kitchen table, where Mortimer was sitting with his laptop. "All right, tell," she said, sitting down and taking a sip from her mug.

"Well, I expected the killer to be from the Denver area, as you know."

Sheila smiled. "I'm not surprised, given that all the murders took place in Colorado."

"So, who in Denver would know enough about checkers to know the openings so well as to be able to set up problem positions from all of the main opening groups? And who would be clever enough to come up with a method of murder that related to the nickname of a particular sequence of opening moves? It had to be someone at the master level, or at least with a lot of background in checkers. That person would probably be an ACC member of some note."

"Go on," Sheila said.

"So I checked the roster. There were only three ACC players in Denver who met the criteria. So I figured it had to be one of them."

"But it wasn't," Sheila said.

"No, it wasn't. I had trouble figuring any of them to be a murderer, but it was all I had to work with. As it turned out, I had forgotten a fourth possibility, someone who definitely had motive. And that's who it turned out to be."

"That guy--- what would have made him do those terrible things?"

"He was a checker player, all right, and a really good one. He was a member of the ACC, but was booted out. He played in a tournament a little while ago, and insisted in playing in the master's division. The ACC wouldn't let him because he had no rating and no track record. He had never played in an ACC tournament before, and they wouldn't let him play in the masters until he proved himself. He got really angry and made a scene. The police were called. The ACC revoked his membership and told him not to come to any more tournaments."

"And that turned him into a killer?"

"Well, not in and of itself. But you know how nerds can be, well, a little unbalanced?"

Sheila smiled again. "Present company excepted, of course," she said.

"Uh... maybe not," Mortimer said candidly. "But at least I'm not a murderer."

"You looked pretty fierce waving that razor around and yelling, 'Single edged razor!'" she said, and couldn't help laughing.

Mortimer laughed along with her. "I guess that was quite the sight," he said.

"But finish your explanation," Sheila said. "It's good practice; I'm sure you'll be repeating it again more than once."

Purdy had of course heard about what had gone on in Aurora, and had called Sheila several times. She didn't answer his calls. Of course, Purdy now couldn't bring Mortimer in as a suspect, but Mortimer and Sheila both knew they'd have to make more statements before the affair was concluded.

"The guy just snapped, I guess," Mortimer said. "Now that he was banned from tournaments, he had no way to show that he really was a master player. So he came up with this scheme to show very deep knowledge and to get revenge on the ACC."

"What I don't get," Sheila said, "is why he just killed random people. None of them played checkers, at least not seriously."

"It was all about the addresses, having the street numbers match the opening moves, the street names match the openings, and the method of murder matching the opening nickname. The victim's identity didn't matter. It was all about the rest of those things, to prove that he was a master player."

Sheila's phone rang again. Purdy. "I better answer it this time," Sheila said, "and then we'll be downtown at the office for quite a few hours. It'll be another late night."

She waited a few seconds, then continued, "Maybe it'll be so late that you'll need to stay over again."

Mortimer laughed and pulled her over to him. The phone continued to ring. "Mortimer, I really need to answer that."

"Call him back," he said, pulling her even closer.

---

Once again, experts may recognize this position and know how to proceed. The rest of us will struggle, but it's a great learning experience and worth the effort. When you're ready to see the solution, click on Read More.

Solution

It's obvious from our story that the position shown occurs in the very tough Black Widow opening. Here's the run-up, in a variant that appeared in Cayton's Compilation as well as other places.

1.	11-16	23-19
2.	16-23	26-19---A
3.	8-11	27-23*---B
4.	11-15	22-18*
5.	15-22	25-18
6.	9-13	29-25*
7.	13-17	21-14
8.	10-17	18-15*
9.	4-8	24-20*
10.	6-9!

10.	...	31-26*
11.	17-21	25-22
12.	9-13	22-18---C
13.	7-11	15-10*
14.	2-7	32-27*
15.	7x14	18x9
16.	5x14---D	19-16!
17.	12x19	23x7
18.	3x10	20-16
19.	8-12	16-11
20.	10-15	11-8
21.	15-18	8-3*---E
22.	13-17	26-23*
23.	17-22	23-19*
24.	22-25---F	3-7 /td>
25.	1-6	7-11
26.	6-9	11-15
27.	18-23	27x18
28.	14x23	15-18
29.	23-27	19-15
30.	25-29	18-22
31.	27-31	15-10
32.	31-27	10-6
33.	9-14	6-2
34.	12-16	2-7
35.	27-23	7-10
36.	14-18	22x15---G
37.	16-20	10-14
38.	29-25	14-10
39.	25-22	10-7
40.	20-24	28x19
41.	23x16

to a clear draw.

A---The Black Widow, with advantage to Black.

B---Anything else loses. The first of a long series of star moves. No wonder this is considered a difficult ballot!

C---32-27 is given to draw in Cayton's Compilation, but it seems to lose: 32-27 5-9 22-18 13-17 19-16 12x19 23x16 8-12 16-11 7x16 20x11 12-16 and White hasn't got a decent move, for instance 15-10 9-13 26-23 17-22 18-15 22-25 28-24 16-20 30-26 and the game is all but over for White. The text move 22-18 is in the KingsRow opening book and appears best.

D---White is a man down but still draws.

E---Not 8-4 which appears to lose.

F---End of KingsRow opening book.

G---White gets his man back and draws!

Sources: Cayton's Compilation, Al Lyman's analysis, and the KingsRow checker engine with 10-piece endgame database.

Yes, this one was tough, like just about all of the problems in the story, but we do hope you got some benefit from this fascinating line of play. Like Mortimer, checkers is full of surprises.

And so concludes our serial, The Checker Murders. We hope you enjoyed it and welcome your feedback.