The Domino Pattern

The intruder had cut a section of safety webbing from the base of one of the crates, picking a strand about ankle height, and had continued his cut all the way around the stack until he’d freed enough slack to reach twice across the most likely aisle for us to take when we came charging after him. He’d stretched the line straight across the aisle, looped it through the webbing on the stack on that side, then run it back to the original stack at about a thirty-degree angle.

The result had been a pair of trip wires with a continually varying distance between them, the sort of arrangement that would be perfect for use against two pursuers with different stride lengths. Odds were very good that at least one of us would hit at least one of the lines, which was precisely what had happened. “Nice work,” I commented. “This guy’s definitely a pro.”

“But how did he set it up?” Bayta asked, frowning as she poked experimentally at the taut line. “He couldn’t have had more than a couple of minutes once he knew we were here.”

“Which means he didn’t set it up then, at least not completely,” I told her. “He must have done all the cutting as soon as he came back here, leaving the loose cord wadded up against the base of the crate where we wouldn’t notice it. Once he spotted us and slipped away around the back of the crate stacks, all he had to do was loop the end through here and tie it down back here.”

“And then lure us into running after him,” Bayta said, grimacing. “We should have known better.”

“We did know better,” I assured her. “I was just expecting a different sort of trap, that’s all.”

“Wait a minute—there he goes,” Bayta said, staring suddenly into space. “He’s left the baggage car and is heading forward.”

“What species is he?” I asked. I knew Spiders usually couldn’t distinguish between individuals, but a species identification would at least get us started.

Bayta frowned in concentration. “He can’t tell,” she said, sounding rather nonplused. “He’s wearing a sort of hooded cloak that’s completely covering his head, arms, and torso.”

“What about his height? His build? Anything?”

“He’s tall enough to be a medium-sized Filiaelian, a tall Human, a slightly overweight Fibibib, or a slightly underweight Shorshian,” Bayta said, sounding rather annoyed herself. This was her plan, after all, that he was outthinking us on. “All the Spider can tell for sure is that he’s not a Pirk, Juri, Bellido, or Cimma.”

I mouthed a foul word one of my French-born Westali colleagues had been overly fond of. “Fine,” I growled. “He wants to play games? We can play games, too. Have the Spiders keep an eye on him. Sooner or later, he’ll have to take off the party outfit.”

“Do you want the conductor to try to pull aside his hood when he passes?” Bayta asked.

“No,” I said. “If he doesn’t already know about our close association with the Spiders, I don’t want to tip our hand. Just have them keep an eye on him.”

“All right,” Bayta said. “What now?”

“We go do what we actually came here for,” I said. Pulling out my multitool, I cut the trip-wire cord and pushed the ends out of the way. Then, getting a grip on the safety webbing behind me, I pulled myself carefully to my feet. “Let’s go look at some dead bodies.”

———

I had hoped there would be a way of telling which and how many of the storage tanks our intruder had broken into. But no such luck. There were no locks on the tanks, nor were there any breakable—or broken—seals. The four bodies lay quietly and peacefully in their temporary coffins, each wrapped like a mummy in wide strips of plastic. “I guess we’ll start here,” I said, gesturing to the coffin which had been ajar when we’d arrived. Swiveling the lid all the way up, I started gingerly unwrapping the corpse.

“What exactly are we looking for?” Bayta asked, her voice sounding a little queasy. “Needle marks?”

“Mostly,” I said. “I’m thinking one of the needle marks may have something different about it.”

The wrapping came free of the head, and I saw that it was Master Colix’s rest I’d disturbed. “Here we go,” I said, working the plastic free of his shoulders. “You want to start on one of your own, or shall we both work on this one?”

“You go ahead,” Bayta said, making no move toward the other coffins. “I’ll just watch.”

“Okay, but this is the really fun part of investigative work,” I warned. Forcing my mind into clinical Westali mode, I leaned into the coffin and got to work.

I’d expected the job to take a while, with a lot more unwrapping necessary before I got anywhere. But as seemed to be happening more and more these days, I was wrong.

“There we go,” I said, pulling Colix’s tunic back to reveal the tiny needle mark a few centimeters below the top of his collar and just to the left of his corrugated spinal ridge. “One needle mark, comma, hypodermic. Definitely fresh.”

“How can that be?” Bayta objected. “The Spiders have accounted for all the hypos the passengers brought aboard.”

“Which means it was either Aronobal or Witherspoon, or else someone managed to smuggle a spare aboard,” I said.

Bayta shook her head. “That shouldn’t be possible.”

“Possible or not, here it is,” I said, gesturing to the body. “Take a look.”

Bayta shuddered, but gamely leaned in a little closer. “Seems like an odd placement,” she commented. “How could someone make an injection back there without him noticing?”

“Actually, it’s a perfect spot,” I said. “Generally speaking, in order for poison to be injected without the victim noticing, he or she has to be asleep, comatose, or drunk. Those third-class nighttime privacy shields have openings at the top for ventilation. All our killer needed to do was go up to Colix’s seat, reach in with his hypo—”

“Did Master Colix use his privacy shield?” Bayta interjected. “A lot of Shorshians don’t.”

I stared at her, then down at the needle mark I’d felt so proud about finding ten seconds earlier. Damn it, but she was right. And if Colix’s whole skin surface had been available, surely the murderer could have picked a more out-of-the-way spot for his injection.

Had it happened at dinner, then? The mark was also in the right spot for someone who’d sneaked up behind him and surreptitiously poked a hypo into his back.

Only that brought us back to the question of how that little trick could have been performed without Colix noticing. A brief twinge of pain he’d passed off and immediately forgotten? A close encounter, moreover, that his dinner companions hadn’t even noticed? “Good point,” I told Bayta. “Let’s think about it a minute.”

Gingerly, I slid my hand down inside the plastic wrappings to Colix’s chest and started feeling around the vicinity of his tunic’s inner top pocket. “What are you doing?” Bayta asked.

“Looking for this,” I said, pulling out Colix’s Quadrail ticket. “I guess the murderer didn’t steal it after all.”

“Then how did he get into Master Colix’s storage compartment?” Bayta asked, frowning at the card.

“Two possibilities,” I said. “One is that he didn’t need the ticket because Colix’s compartments were never locked that night.” I wiggled the ticket between my fingers. “The other is that that’s precisely what our intruder was doing back here just now. He’d taken the ticket, used it to open the compartment and steal Colix’s goodies, and was hoping to return it to its rightful owner before we came looking for it.”

“That has to be it,” Bayta said. “Master Colix was very possessive of those snacks. He wouldn’t have left them unlocked where they could be stolen.”

“Not so fast,” I warned her. “We also know that the compartment was unlocked the next morning, when Tas Krodo returned Colix’s blanket.”

“Which only means the killer must have left it unlocked after he stole the snacks,” Bayta countered.

“Or else that Colix was already feeling too sick to bother locking it after he got out his blanket,” I said. “But that brings us to another interesting point.” Sliding Colix’s ticket into my own pocket, I reached back down to the body, loosened the braidings tying up the front of his tunic, and pulled the collar all the way down. “As the French say, voila,” I said, pointing to the faint parallel scars running lengthwise along his throat on either side of his larynx. “Twenty to one those are the marks of the infamous Gibber Operation.”

“The what?” Bayta asked, frowning as she leaned over for a closer look.

“It’s an operation the Shorshians don’t talk much about,” I explained, resisting the temptation to point out how