Mike Shayne Mystery Magazine, Vol. 34, No. 5, April 1974

The Drop of a Pin by Christopher Anvil

Her uncle was murdered and the door was locked in three ways. No one could have done it and escaped — could they?

The copper dazzle of the setting sun on the lake momentarily blinded Richard Verner as the sheriff, at the wheel beside him, turned the car off the road onto a graveled drive that wound beneath tall hemlocks. To their left, a large sign spelled out, “Grove’s Lake Cabins.” The sheriff braked as he swung to the right, to park in front of a cabin with two large front windows, and two separate front doors, one near either end of the cabin. Above the right-hand door was a small sign lettered Office.

The sheriff shut off the engine, and looked somberly at the cabin.

“Grove’s body was in the right half of this double cabin, flat on his back on the bed with a knife through his chest. His niece lived in the left half of the cabin. She reported the murder, and her own story, and the evidence, show that she must have killed her uncle. I’ve had to take her in. But I don’t believe the evidence.”

“Why not?”

The sheriff shook his head. “I know people. She didn’t do it.”

Verner glanced around at the cabins widely spaced beneath the trees, and looked again at the cabin near the car. “Before I do anything, I have to say again, I’m not a detective. You realize that?”

“I know it. You’re a—” The sheriff shook his head. “I can’t say the word.”

Verner said, “Heuristician. It means a specialist at solving problems. I’ve developed the skill well beyond the usual level, but this isn’t the same thing as expert knowledge. I don’t want to go near this cabin unless you already have every scrap of useful evidence the cabin will yield.”

The sheriff nodded. “One of my deputies is a one-man crime laboratory. He’s taken photographs in there from all angles, collected blood, fingerprints, dust, threads, and cigaret ashes, and he doesn’t know what to make of half of it, and neither do I. Anything you do with that cabin, short of burning it down, is okay with me.”

“Good. Now, tell me again what you said on the phone.”

“At about six-fifteen Monday morning, I had a call from Ellen Grove. She said she had just found her uncle dead on his bed, with the door and windows locked. This cabin has a large room and bath in either end, separated by a heavily insulated wall with no door in it. Ellen had promised to wake her uncle early, couldn’t rouse him, got worried and used an electric saw to cut through the insulated dividing wall, between the two bathrooms.”

“Why did she do that? It sounds crazy.”

“You don’t know Ellen Grove’s uncle. It was the beginning of Grove’s busy season. To smash a door or window would have made extra work. All it would take to repair the opening she’d cut would be to put up a small section of insulating board, and meanwhile the damage wouldn’t be noticeable.”

“When you got here, then, the cabin door and windows hadn’t been touched?”

“Right. I went through this opening, found Grove flat on his back on the bed, a knife through his chest, a bump on his head, and blood all over the floor. The knife-wound looked as if it had killed him instantly. There was no note, nothing to suggest suicide, and from the blood and traces of wiped-up blood, it was clear he wasn’t on the bed when he was stabbed. It follows, somebody put him there.

“Well, the door was locked and bolted with a safety chain on it, and the windows were all locked from the inside. Standing there looking around, I couldn’t help asking myself how the killer got out. By Ellen Grove’s own story, she cut through the wall, went into this heavily locked room, and found the body on the bed. No-one else was there. There’s the problem, Verner.”

“Ellen Grove called you about six-fifteen?”

“Right.”

“How did she find out so early that her uncle had been killed?”

“Grove was a very heavy sleeper. He’d asked her to wake him if he wasn’t up by five-thirty. She rapped on his door, called, and there was no answer. There’s a doorbell in case a guest gets in late, but it was out of order. She was afraid when she couldn’t wake him, wondered how to get in without doing a lot of visible damage, then remembered the electric saw he’d used working on a new cabin.”

“There was no opening in the wall until she cut through it?”

“None.”

Verner looked thoughtfully at the cabin.

“The left side is Ellen Grove’s? The right side belonged to her uncle?”

“Always.”

“Did he have any enemies?”

The sheriff smiled. “He had more enemies than anyone else I know of around here. I was one, myself.”

“Why?” Verner asked.

“He had a flash temper, a tongue like a poisoned dagger, and he would nurse a grudge. Several years ago, he had trouble with a drunk, and called me up just as I was on my way to a pretty bad accident. We were short-handed, and I went to the accident first. Grove lever forgave me. He had a lot so say about electing a sheriff and getting an ambulance chaser. He backed my opponent in the last election, and he was backing the fellow they dredged up to run this time.” The sheriff shook his head. “Not that anyone could blame him for backing his own cousin, however worthless the— Well, that’s beside the point.”

Verner sat back, frowning. “What is Ellen Grove like?”

“Quietly pretty, and very hard-working. She’s a nice girl.”

“She stayed with him all the time?”

“Yes. He was her guardian. Her mother and father were killed in an accident about ten years ago.”

“He had no children of his own?”

“No, and these cabins are worth a lot now, she stands to inherit them — and that, you see, provides a motive, especially since she’d wanted to marry a boy who was just drafted, and Grove refused to give permission. True to form, he had a big fight with the boy, called him all kinds of names, and threw him off the place.”

“Where was he when Grove was killed?”

“Two thousand miles away, in an Army camp.”

Verner looked at the cabin in silence, his gaze remote and speculative.

“The cabin is solidly built?”

“I’ve gone over every part of it. The floor and ceiling are solid, and the walls are just as solid.”

“Then, the door was locked in three different ways, the windows were locked and the screening intact, and the floor, walls, and ceiling were solid?”

The sheriff nodded.

“What chance is there that as she used the electric saw, the murderer hid in Grove’s bathroom — and when Ellen Grove went past into Grove’s bedroom, the murderer stepped out through the opening she had made, and left the cabin through her door?”

The sheriff shook his head regretfully. “That was another triple-locked door.”

“Do you mean that Ellen Grove, when she brought in the electric saw to cut through the wall, stopped and set the saw down in order to lock the door three times behind her?”

“That’s it exactly. You see, Grove was a fanatic about having doors locked at night. Ellen was worried about cutting through this wall, but she was worried about her uncle. She wasn’t thinking too clearly. She remembers setting the saw on a chair by the door of her room, methodically closing the screen door and locking it, just as she would do at night, then closing the inside door and locking the lock, sliding home the bolt, and fastening the chain. And that’s how it was when we got here. Exactly the same as in Grove’s end of the cabin.”

“The screen door, too, was locked from the inside?”

“Didn’t I mention that?” said the sheriff. “Yes, both screen doors were locked from inside. There’s a little lever inside that moves up and down to work the lock. There’s no arrangement for locking them from outside.”

“Then we have two locked doors, one behind the other?”

“Right. And another identical set in the other end of the cabin.”

“How long was Ellen Grove in her uncle’s end of the cabin?”

“Long enough to see what had happened, and to make the phone call.”

“Three or four minutes?”

“Yes, I would say at least that long,” the sheriff replied.

“Were the shades up or down?”

“Down.”

“Did she examine the room?”

“No.”

“When she phoned you, she mentioned that the windows were locked?”

“Yes.”

“How did she know?”

“When she was outside trying to wake up her uncle, she tried the windows.”

Verner nodded. “All right. Let’s take a look at those windows first.”

The sheriff handed Verner a five-cell flashlight to augment the fast-fading light of day, and, one-by-one, they examined the windows. Each one was covered with screening tightly stapled to the window frame, and painted over along the edges so that there remained no place not sealed to the frame. Verner closely examined the screening, and the frames around the windows, then walked slowly around the cabin, shining the light over walls finished with clapboards solidly nailed down, and painted dark-green.

He shone the light along the base of the cabin, built on wooden piles set in the ground, with a tight barrier of dark-green wooden strips to keep out animals. At the back, beside a tank of bottled gas, was a loose section of this barrier. Verner lifted it out with a faint tearing sound, to find an opening thickly covered with spider webs.

He walked slowly back to the front of the cabin, to look at the doors. The screen door by the little sign reading Office was locked. The sheriff swung the other screen door back, unlocked a plain paneled wooden door, snapped on the light, and they entered a cozily furnished girl’s room, where a trace of light perfume lingered in the air.

Verner glanced alertly around, then followed the sheriff through a small dim bathroom, past a tall narrow piece of wallboard leaning against a shower cabinet, through the opening in the bathroom wall, and out through another bathroom. The sheriff snapped on a light, and Verner was in a room where a large desk sat beside a rack of keys hanging from the wall. There was an old-fashioned safe in the corner of the room to one side of a bed covered with a sheet. On the other side of the bed was a night-table bearing a lamp, a phone, and an alarm clock. Directly above the bed was a doorbell, its two wires running down out of sight behind the head of the bed.

Verner looked at the door. It had the key turned in the lock, and a safety chain fastened so that the door could be opened only so far. On the door was a large bolt, whose end fit not into the usual type of thin metal fixture but into the curve of a heavy U-shaped rod of steel set into the wood itself.

The sheriff said drily, “That door is locked.”

Verner examined it closely, to see a slight gouge in the wood, where the bolt passed through the steel U. He slid the bolt back and forth, and it hissed lightly against the steel but didn’t touch the wood.

The door was painted a light cream color, and was old-fashioned, very plain, with thicker sections of wood between the panels. These thicker sections crossed the door from one side to the other, like the rungs of a ladder, and were square-edged, without trim or beveling of any kind.

“This door,” said Verner, “is an inside door, isn’t it?”

“Yes. That came from a house that was torn down when they put the new highway through. You see, with that highway, we expected tourists. Grove bought the doors and windows from the house and used them when he built the cabins.”

“This is lighter than a regular outside door?”

“It’s lighter weight. To do justice to that bolt, Grove should have had a solid oak door. But, that door wasn’t broken down. It tells us nothing.”

Verner shook his head. “Look at the dent in that wood just back of the place where the bolt slides into the U.”

The sheriff bent to study the spot, slid the bolt carefully back and forth, and straightened up, frowning.

Outside, there was a crunch of tires on gravel.

The sheriff murmured, “A tourist, probably. I’ll go out, and—”

Outside, there was the rapid click of a parking brake, then the slam of a car door. A rough male voice shouted, “Anybody home?” There was the sound of heels on gravel, a brief silence, and then a hammering on the other door of the cabin.

The sheriff growled under his breath, reached out to unbolt the door, but Verner stopped him, to speak in a whisper.

“Grove’s cousin?”

“Himself. How did you know?”

“If what I think is true, two minutes alone in here will give him the perfect crime. But the only safe way for him to get in is to come when you’re here, and decoy you outside.”

“You want him kept out?”

“No. Don’t tell him anyone else is here. Let him in by the other door, and give him time to get into this side of the cabin. Then come back in and shout to him to come out.”

Outside, there was a jaunty whistle, a crunch of heels on gravel, then a shout. “I want to get out of the road here and park. I’ll be right back.”

There was the roar of an engine, a whine of tires and a rattle of gravel, then the metallic bang-crash of one car slamming into another.

“Damn!” cried the voice. “You were in my way!”

The sheriff swore under his breath. “Can’t even drive and he wants to be sheriff.” He walked toward the, other side of the cabin.

Verner followed into the dimly lighted bathroom, stepped into the shower cabinet and pulled the plastic curtain along its rod so that nearly all of the shower was visible except where he stood. Then he waited.

From outside came a loud complaining voice. “You were parked crooked!”

“Crooked?” came the sheriff’s voice, thick with anger. “Do you think this is a parking lot? Can’t you watch where you’re going? Where did you hit it?”

“Doesn’t look like there’s any damage done! Or if there is, I’m good for it. You check her over. I’ve got to get some stuff Ellen wants.”

There was the sound of the cabin door opening, then rapidly approaching heavy footsteps, the sound of hoarse breathing just behind Verner, then the opposite side of the shower stall lit up briefly as a light shone quickly around the bathroom. The sheriff called from outside, “Where are you?”

There was a brief grunt, then the heavy footsteps went into Grove’s room.

There was a moment’s quiet.

Verner stepped softly out, to glance into the room.

At the front door of the cabin, he saw a squat figure in a worn hunting jacket at the door’s lower edge.

Silently, Verner stepped into the room behind him.

In the other end of the cabin, the sheriff called angrily, “Come out of there!” The sheriff’s purposeful stride grew suddenly loud.

Verner watched as a small hammer disappeared into the hunting jacket. From the rough figure came a little chuckle, a quick “Yes, sir!” and then the man shot back the bolt, twisted the key in the lock, and snapped the chain free.

Verner blocked the bathroom door with his foot, and threw his weight against it, holding it shut despite the other man’s advantage in leverage. There was a rough intake of breath, and Verner was looking into a pair of eyes that glinted with cunning.

Across the room, the sheriff shouted, “Hold it! What’s this?”

The squat figure gave a sudden powerful wrench at the door, jerked it partly open, leaned outside, and then abruptly he was back in the room, glaring triumphantly.

“If I want, I’ll go out! All right, who are you? What are you doing here?”

Verner stepped back from the door, very slightly stooped, his motions relaxed and somehow suggesting the movement of a big cat.

There was a brief tense hesitation.

At the door, the porcine figure stepped back, fists balled.

Verner’s hand shot out, to slam home the bolt.

Verner said, “He took the hinge pins out and replaced them. He just threw them outside. You might as well arrest him for the murder of his cousin.”

In the beams of the parked sheriff’s cars, the deputy handed back a piece of shining metal, similar to a large nail, but less pointed on the end. The deputy shook his head.

“He must have rolled that one in his hand when he threw it. There was oil on it, and about half his right thumb print.” The deputy frowned as he looked at the hinge-pin. He cleared his throat, but the sheriff spoke first, to Verner, his tone crisp and confident.

“All right, we’ll go back inside, and see if this checks out.”

They entered Grove’s side of the cabin, and the sheriff shut the door firmly. With an odd expression on his face, he looked at the hinge-pins. He glanced at the door, then at Verner.

“This may be clear to you. But what good did it do him to change the hinge-pins?”

“You remember the little dent in the wood under the U-shaped receiver?”

“Yes. I don’t see how it got there. The bolt slid past it without touching, and that U would protect it from being bumped.”

“Suppose the bolt did make that mark? What would that mean about the position of the door?”

The sheriff touched his chin. Suddenly his eyes widened.

“The hinge side of the door would have been away from the door frame, and lock side against the frame... The door would have been partly turned on that bolt as if the bolt were the hinge!”

“And what,” said Verner, “would that say about the hinges?”

The sheriff glanced at the door, which had the standard type of butt hinges. Each hinge was made in three parts — a vertical pin which served as a pivot, and two separate metal plates, one attached to the door, and the other to the doorway. Each plate bore curving pieces of metal which clasped the pin. With the pin removed, the plates would come apart.

The sheriff shook his head. “I’ve been looking at the wrong edge of this door.”

He unlocked the door, took out a big pocket knife, and, using the screwdriver blade of his knife, worked loose the pins, which were somewhat thicker than the others, and less shiny, with blunt ends. He called a deputy, and dropped out the pins in a box.

“Check these for prints, just in case.”

He set the lock side of the dismounted door near the lock side of the frame, and steadying the door with one hand, connected the safety chain, pushed the bolt all the way out, and turned the key in its lock so that the lock bolt slid out. He lifted the door by the wooden crosspieces, eased it into the doorframe, the bolt sliding into its U-shaped rod, the lock-bolt sliding into its hole, and the chain, already fastened, clinking against the door. The hinge-halves bumped together, the sheriff worked the door slightly up and down, and first the lower and then the upper hinge slid together.

“Now,” said the sheriff, “we need to have the hinge-pins in. Since they fit in straight up-and-down, they’ll drop of their own weight, if they’re held upright just in the top of the hinge, and if they’re ground down a little and oiled, like the pins that were in this door. But, how could he hold them upright on the inside while he was outside working the door back into place?... Let’s see... Yes, a little thread would do it, looped around the hinge-pin and tacked outside the door.”

The sheriff took the hinge-pins, held each in turn at the top of its hinge, and released it. Each dropped partly into place, then stopped. He worked the door back and forth, then lightly rapped it with his fist. The hinge-pins dropped into place. He unlocked and opened the door, took the bedside lamp on its long extension cord, and carefully examined the hinge side of the doorframe.

“Look.”

Verner saw a tiny hole, above and outside of each hinge, made apparently by a pin or tack.

They examined the screen door, to find a little vertical groove in the wood at the top of the door, directly above the lock lever, and a corresponding groove at the bottom of the door directly below the lock-lever.

“A piece of strong Nylon thread,” said the sheriff, “wound around that lock lever, and run out the top of that screen door, and the other end run out the bottom, would do it. If he drew on both ends of the cord, the thread would hold tight around the lever. He could pull down from outside the door, and lock the lock. Then if he let go one end of the thread, and pulled on the other, the thread would slip free and slide out. The same with those hinge-pins. Once he was outside, all he had to do was to hold one end of the thread, and let go of the other end. The hinge pin would drop down partly into place, the thread would slip free, he could rattle the door a little to work the pin down all the way, and the door would be locked, with him outside.”

The sheriff grinned suddenly, and looked at Verner. “Now that you’ve got it worked out, I can explain it. Now, let’s try it, from outside. Here, you start these pins, after the door’s in place.”

This time, the sheriff stepped outside past the opened hinge side of the door, gripped it by the crosspieces, drew the door into its frame from outside, rapped it lightly and repeatedly to drop the hinge-pins into place — and the, door was locked from inside, while he stood outside.

He came back in, smiling. “Now we know how, but not why. They were cousins, and Grove was backing him. Why would he kill Grove?”

Verner shook his head. “You know the people, and I don’t. But you say Grove had a flash temper, and could be a bitter enemy. I’d guess Grove was mad at him, or he expected Grove was soon going to be mad at him.”

The sheriff nodded.

“There was talk he’d been behind in his mortgage payments, but he straightened that out. If Grove lent him the money and he couldn’t pay it back—” The sheriff shook his head. “There was one man you never wanted to owe money to unless you paid it back on the dot.”

“He was Grove’s closest relative after Ellen Grove?”

“Yes.”

“Then,” said Verner, “at one blow, he could eliminate Grove; very possibly eliminate Ellen Grove as the person who would inherit Grove’s property — since she was likely to discover the body, and be the apparent murderess; clear up his own money troubles; and possibly, if the trial went badly, strengthen himself politically at your expense. But that’s only a guess.”

The sheriff opened the door and called to his deputies, who brought in the squat dejected figure, eyes downcast, shambling. The deputies, however, were alert and wary.

The sheriff nodded toward a chair. His voice was soft. “Let him sit there. As long as he doesn’t do anything, keep your hands off him.”

“Sheriff, I think we need handcuffs.”

“I don’t. Okay, Eb, what happened here?”

The dejected face looked up, eyes squeezed shut. Abruptly the eyes opened, and blazed.

“He called me ‘Corkscrew.’ He said I’d pay him the money, or he’d make me the joke of the county. ‘Corkscrew for Sheriff— Always in the liquor and as crooked as they come! Vote for Corkscrew!’ I don’t know what happened to me. I took a swipe at him and missed. He slipped, and hit his head on that rail at the foot of the bed there. He came up with that knife in his hand, and said, ‘So long, Corkscrew,’ and the next thing I remember, I’d finished him.

“I stood there looking down at him, and I started for the phone, and then it hit me nobody would believe my side of it. That’s when I saw those hinge-pins laying on the bed. I was in a daze. But I thought I saw how I could fix it so no one could get blamed, since no one could have gotten out.”

The sheriff said mildly, “How did the hinge-pins get there? You mean, Grove had put them there?”

“He threw them there. He’s complained that this door here gets rusted with the dampness over the winter, or the pins are too tight, or there’s something wrong, because at the start of the season, it squeaks, and he never gets around to oiling it. When I couldn’t raise the money to pay him, I tried to think of something to take the edge off his temper — you know how he was — so maybe he’d listen and give me a little more time.

“I thought, he’s always complaining about those squeaky hinges, maybe it will get him in a better mood if I fix them. Well, I came in and smiled, and I said, ‘I brought you something to fix those squeaky hinges,’ and he looked at the hinge-pins, and he looked at me, and he tossed the pins aside and said, ‘That will keep. Let’s have the money.’ Well... you know the rest.”

After the deputies and their prisoner had gone out, the sheriff glanced toward Verner.

“What do you think? According to that story, it’s self-defense.”

Verner shook his head. “I’d check to see if those oiled hinge-pins left any mark on the bedspread. What do you think?”

“There was a little oil on that bedspread. What I think is that we’ll have a hung jury between those that want to send him up for life, and those that want to give him a vote of thanks for doing what they felt like doing themselves. Well... Ellen’s out of it, and we’ve got the actual killer. You still say you aren’t a detective?”

Verner shook his head. “I’m not a detective.”

The sheriff smiled. “I don’t know anyone better qualified to be one. I give you an impossible triple-locked door. And you hand me back an open-and-shut case!”