"Take a closer look at that window," said the constable, gesturing. "Only the top-left pane was cracked. Why? If they were simply trying to break in, they should have gone for one of the lower panes. Or even one of the panes in the middle row, if they couldn't tell where the latch was. But surely even the most amateurish of robbers wouldn't think that a window opens at the top."

She examined the body – third one so far. A single splash of blood, and then a long smear, as if something had been dragged away. Very curious.

Beside her, the local inspector hovered anxiously – his curiosity soon becoming impatience as she showed no sign of wanting to discuss the case. "Ahem. Ahem. Ahemmmm. Ahem," he tried, to no avail. His concerned assistant offered him a cough drop instead.

"But that means... 7.30 p.m..."

He paused. "Or, wait, a mirror image? 4.30 pm, surely?"

That image surfaced in his mind again: the body's strange sprawling stance, that outstretched hand... If only the boatswain hadn't gone missing as well, he thought.

The detective glanced at the late stockbroker's colleague, who had curled his fingers along the top of his thumb and was inspecting his fingernails with an air of extreme boredom.

"Look here, sir," he began. The witness was now buffing his nails against his suit lapel, his thumb resting between his ring finger and pinky.

This wasn't the job I'd bargained for all those weeks ago. Each click of her high-heels on the grimy concrete was like the echo of a coolly-discharged gunshot.

"Calm down, Romeo," she breathed, like something which breathes in an ominous yet compelling manner.

"That Yankee officer you're looking for..."

"A thousand?" she asked, trading an incredulous glance with the sergeant. "No wonder your employee left. And it took your company this long to come to the police?"

"Yes, yes, okay, yes, I know, it sounds ridiculous, but you have to understand the constraints the team was working under..." Beside her, the sergeant rolled his eyes discreetly.

The lab held few traces of its erstwhile occupant, but suggested plenty of chaos, she thought, stepping forward and nearly tripping over a retort stand that was lying unceremoniously on the floor. Scattered papers damp with some suspicious liquid. Shards of broken glass everywhere – very dangerous, someone had better look at it. A cracked jar lay on its side, flooding the bench with still-brown iodine.

"Not a very... relatable fellow," said the firm director. "The sort who drinks tea with their pinky sticking out, you know. Posh. Rhymes with banker."

"Quite," said the detective, glancing at the photos on the dead man's desk. In one of them he was giving the photographer the fig sign. "Well, let's meet the rest of his team."

Yes, the sculpture heist had been unexpected, to put it mildly; but the disappearance of the museum director, a mere week later, was even more so. "Obvious signs of a struggle," the constable said, holding up what had once been a smart double-breasted coat. Four of its buttons had been torn off, leaving just one on the top-left and one on the bottom-left.

"Yes... Yes... No, no, look here, I said–"

Deciding to leave the manager to his phone call, she headed over to where the sergeant was inspecting the missing programmer's desk. It was a mess of wires – someone clearly hadn't heard of cable management – but more curious was the overloaded multiplug. Every surface had something plugged in, yet only the first two sockets were switched on; the other two were switched off.

He glanced at the dead man's shattered watch face: 7:15.

The late shipman's left arm was flung out to his left and above his head, as if waving; the right arm, in contrast, lay oddly straight by the body's side. "Well then," he said, standing back up. "Let's start talking to the crew, shall we?"

I knew it was going to be a busy day for the Mike Noir Detective Agency.

That's me, by the way. The rain was scouring the city like an overzealous washerwoman and the newspaper's front page had some old Yankee officer disappearing in suspicious circumstances. Suspicious.

"What had the professor been working on?" she asked. The lab assistant glanced around nervously; then, satisfied that no one else was around, replied: "Ah, well, she was into molecular gastronomy, recently: hot water baths, liquid nitrogen, all that sort of stuff. She used to say that if science didn't work out, she could go into the food business!"

"Couldn't just rob us, had to leave their mark, too," the museum director said with an angry gesture. The investigation team contemplated the spray-painted front door: three splotches, crudely forming a right-facing arrow. After a few moments, the museum director sighed. "Let's take a look inside, shall we?"

The sergeant frowned, recalling what they had seen earlier. "You're saying he always left the switches on? All four? All the time?"

"Yes... No, okay, yes, correct..." The janitor broke off, nervous.

"Let's see," muttered the boatswain, checking the log. "West and southeast..."

He flipped the page. "Yes, and then west and southeast again. Bizarre."

She was a classic femme fatale. Very femme, very fatale. They said she was called Sierra because she was as frosty as the mountains and about as likely to kill an unprepared man.

I put my shoes up on my desk for the classic detective silhouette. "Takes two to tango, Miss."

She blinked once, slowly. "What do you mean, they haven't found the light source? This is the fourth murder!"

She rapped the table, a single sharp crack; the inspector shifted nervously.

But then, behind them – a high-pitched beep, a digital squeal, another beep. The tension in the air had been cut as cleanly as that poor second murder victim's throat. They both turned to stare at the hapless assistant, who was swiftly but all-too-belatedly switching his mobile phone to silent mode.