Welcome to Baker Street

84. Out of breath

"Murder?" The baffled question comes from a short, moustached police officer from the Chiswick department. He glowers at the three intruders on his crime scene and towers over the black-haired man knelt by the corpse. "It may simply be a tragic coincidence, sir," the newcomer protests.

Sherlock scoffs. "Oh, please. This death was as accidental as the rise of the sun this morning. I find it quite alarming that the police still believe in fairy tales and signs from the universe."

The officer freezes at that exhibition of blatant disrespect. "Excuse me, you are...?"

"Way more observant than you, Sergeant," Sherlock retorts, straightening up and eyeing the sergeant rank insignia on the upper sleeve of the man's uniform. "For I noticed the obvious and crystal-clear clues of homicide, and you didn't."

"What do you mean 'homicide'? As you can see, this poor man is still wearing the oxygen tanks, diving mask and flippers," the policeman objects, pointing at the corpse.

Sherlock shoots him a disdainful look. "And your foregone conclusion is that he drowned while diving, correct?"

"Well, yes, obviously," the sergeant replies.

"Wrong," Sherlock exclaims while his eyes scan the body from head to toe. "He wasn't diving at all. To be exact, he wasn't even immersed in water when he died."

"What? And how do you explain his equipment, then?" Lestrade intervenes.

"It's another play pretend from our criminal mastermind. Look at the level of oxygen in the tanks: 100%, completely full. Had he been diving, he would have consumed a bit of oxygen, if only to draw the first gulps before kicking the bucket. And yet, his tank looks as if it were taken straight from the rack and stripped to the back of his body."

Giulia chimes in their banter, "It means he wasn't alone here. Since he didn't inhale the oxygen of the tank at all, someone else must have forced the mouthpiece into his mouth when he was already dead. That wasn't an unfortunate accident: it's homicide coupled with the intention to mislead. Or, in your case, entertain." She rolls her eyes at the consulting detective.

A hint of a smile lifts the corners of Sherlock's mouth as he nods at her.

"But even admitting he wasn't diving before dying, how could you say that he didn't die in the water?" the Sergeant struggles to follow that counterintuitive reasoning in the face of such hard evidence.

Sherlock sighs and bends down on the body; he delicately lifts one of the man's arms to show them.

"Look at his hands: no wrinkling of the skin on the fingertips or palms. We all know that when we swim for a prolonged time, our fingers turn all pruney because of vasoconstriction. In other words, the blood vessels located just below our skin shrink. It's an involuntary response of the nervous system, meaning it happens automatically when the nervous system functions properly. However, if the blood isn't pumping anymore and brain death has occurred, the vasoconstriction isn't triggered, and the skin doesn't wrinkle. This man isn't showing any; look at the smoothness of his hands. Conclusion: he wasn't in this pool when he died."

"It still doesn't prove he was murdered. Maybe he was about to take a dive; he was all set with the equipment when something happened. Perhaps he had a heart attack on the edge of the pool and collapsed into the water. This would explain both the full tank and the absence of wrinkling on his skin," Lestrade objects.

"Interesting theory, Detective Inspector. There's just one big problem. I already told you: this man wasn't a diver. He could not be—not without taking quite the risk, according to some diving medical researchers," Sherlock wanders off before being interrupted by Greg.