Watson limped slowly along the tow path, his cane beating out his stride like an echo of his footfalls.

He paused beside the water's edge where only hours ago the Cessarine Majeste had rode at anchor; now, only fragments of wood floated on the oil-slicked surface of the dark waters to betray where once she had been. He stared into the water for a while. He could understand how Holmes had found an almost hypnotic attraction to it; after a while the pattern on the surface made by light playing off the swirls and eddies seemed to almost draw one in, in spite of one's self. He gave a brief shudder and turned away.

He moved away towards the spot where he had been found. He and Irene had been thrown further than Holmes by the blast; he scoured the area carefully with his eyes looking for any signs or clues there. Irene apparently had disappeared before the police found him; at any rate, certainly he had been found alone. Whether Irene had left of her own volition or otherwise, he had no idea. A splash of colour caught his eye; it was a ragged square of cerise taffeta silk torn from a sleeve, caught on a corner of the remaining wall. Striding closer, he plucked it free, examining the dusty fragment carefully. It still held a faint trace of Irene's Parisian perfume. Straightening up, he glanced around, but there were no other signs that the woman had ever been there at all. He hoped that wherever she was, she was not too badly hurt, though Irene had proved herself more than capable of looking after herself on more than one occasion – and to all intents and purposes, it did rather appear that once again she had fled to save her own skin and left himself and Holmes to fend for themselves.

So much for all her protestations of being concerned for Holmes then.

Turning, he limped back towards the last place he had seen Holmes, close to the water's edge, eyes sweeping over the ground relentlessly as he approached the canal once more, putting Irene from his mind for the moment. She had already caused him trouble enough.

The edge of the tow path here was damaged, the paving slabs thrown up and back from the water's edge by the force of the blast. A nearby brick shed had collapsed; Watson limped slowly passed the scattered bricks and segments of wall, barely sparing it a glance -

And then stopped, as something caught his eye. Something small, bright and shiny amongst the wreckage of the wall. He drew closer, finally dropping stiffly to one knee as he reached out to gently lift up a pocket watch.

Holmes' watch. He would have known it anywhere; how often had he seen it in the hand of its owner? By some miraculous chance, it was unharmed and still ticking. He stared down at it in the palm of his hand for long minutes, then reverently closed it and tucked it away safely in his inside pocket.

He turned his attention to the rubble, trying now to see it as Holmes would have done.

He wondered how he had missed the unmistakeable signs that a body had lain here – bricks and stonework moved aside to lift up a body. The splashes of blood there, denoting where the injured head had bled whilst lying insensible; the amount made his stomach turn slightly, but he calmed his unease by reminding himself that head wounds often bled out of all proportion to their severity and it was no indication of life or death in itself. He touched his fingers to the blood; mostly dry but a few damp patches still here and there.

Holmes had been alive when he was lifted from his temporary tomb, of that Watson was certain – and the traces he could see around showed him that he didn't leave by himself. As he looked now with keener eyes for those tell-tale signs which Holmes would have read as easily as a page from a book, he could start to slowly recreate the scene in his own mind. Here, the mark of a walking stick where its owner had leaned upon it, leaving its round imprint upon the dirt. A scuffed paw print; a small terrier of some breed or other; doubtless Holmes could have told him its precise size and maybe even breed from the spread of its claws.

There, the boot print of walking-stick man, the toe blunt and square. And here, the press of a different boot, round-toed and hobnailed. There were other prints, but they were too blurred and confused to distinguish easily, unlike those two marks.

Hunting a little further out and around the pile of rubble, he found what he was looking for – the trail of a toe digging a faint line through the dirt where an injured man had been half-carried, half-dragged away from his resting place. He followed it step by step as it led away from the water towards the back of the factory and around to a side street, where the trail ended by the marks of the wheels of a 4-wheeled carriage drawn by a pair of horse.

Holmes had to be alive; why else would he have been brought away from the rubble? He'd been upright between two men; not the manner in which a corpse would be carried. Which means that wherever the carriage had gone, it had born the living body of the detective.

With growing excitement, he followed the trail left by the wheels of the carriage until the side street joined the main road, whereupon the wheel marks disappeared into the traffic. He stood on the street corner, staring at the hectic flow of carts, carriages, hansoms and omnibuses that dashed past in both directions and struck the pavement hard with his cane in frustration.

It couldn't end here. But how on earth to pick up the trail?

And then a slow smile broke across his face.

"Old Toby!"

Striding out into the street, he raised his cane and flagged down a passing hansom cab. Climbing up into the seat, he called out, "Pinchin Lane, Lambeth – and be quick!" he ordered, rapping upon the roof with his cane.

"Right you are, Guv!" responded the cabbie as he whipped up the horse, and they were off.