Posted by John H. Watson

Jonas Greenwood's house was old-fashioned, grey and made of stone, but had a new garage and extension. There were two large windows in the old part of the lower level, and two dormer windows in the upper level, each sheltered by a triangular hood. There must at least have been an attic of some kind, because the slated roof itself sported two velux windows. The house had two chimneys in the old part, each at either end of the roof. The extension appeared to be made of concrete, painted white, but with small, old-fashioned, wooden windows set in it.

The garden was surrounded by a high hedge and was very large for London, making me suspect, given the economic climate and Greenwood's job as a builder, that this was a family house, passed down through the generations. The lawn was well-cut and the flower beds looked trim and healthy. There were even a couple of trees and several shrubs and bushes opposite the house. I saw the wooden tool shed the article had mentioned, as well as the ashes of the dreaded bonfire. I tried to distract Sherlock's attention before he registered them.

Lestrade and Jonas Greenwood were waiting for us in the kitchen, which was, once again, old-fashioned and wood-themed. Greenwood himself was a large man, but the largeness was mostly in his build; he was not conspicuously tall. He had not aged particularly well, and walked with a slight stoop that possibly came more from a reclusive temperament than some kind of physical pain or stiffness. His hair was grey, but there were still faint traces noticeable of the strawberry-blonde colour it had once been. He had the whiskery beginnings of a beard, a roman nose and thin, white lips. His eyes were small and cagey, yet a clear blue, and he had a quiet, husky, rather uncertain voice with a well-refined accent.

"What?" Sherlock asked as we entered the kitchen.

"This." Lestrade held up a clear plastic wallet in which the 'damning evidence' had been secured. Sherlock plucked the bag from Lestrade, irreverently tore it open and pulled out a small, sharp, wooden-handled knife. Dried blood was caked on the blade, and mixed in with the encrusted putty on the handle there was an unmistakably clear and uniform blooded thumb print.

Lestrade cut in on Sherlock's thoughts. "We took a fingerprint from Macfarlane this morning. It's a perfect match."

"Oh, interesting," Sherlock muttered, staring at the knife with a blank expression.

"Interesting? It's proof!" Lestrade seemed indignant at Sherlock's noncommittal response.

"It's final alright," said Sherlock, but his eyes and his voice were odd. He turned his face away – which is invariably sign that he's struggling with some emotion or other. "Excuse me…" And with that, he marched out the room.

I jumped up and hurried after him, ignoring Lestrade's protests. Once through in the hall I closed the door. I was about to ask Sherlock whether he was coping, when I saw that he was doubled over, quivering, fingertips pressed together tightly over his lips, with one of the biggest grins I had ever seen plastered across his face.

"What's going on?" I demanded.

"I knew it. I KNEW it!" he whispered, in extreme excitement.

"Knew what?" I demanded impatiently.

"That there was something not right. C'mon John…" and with that he rushed out the door in a whirlwind of activity.

"What are we doing?" I asked hurrying after him to the extension. "Finding evidence." He turned to look at me and saw my blank expression. "Still as slow as ever," he muttered, before hastily adding, "The knife, John. It had putty on it. He'd been repairing the windows with putty."

"So?"

"Putty's malleable. Very convenient for making fingerprints in. That's not the only odd thing. The knife had blood on the blade – it had been made to look like Molly had been stabbed with it – "

" – Made to look like it?"

"Yes." He was speaking breathlessly, and as he did so he dropped to his knees and started scooping handfuls of soil out of the shrubbery pots, one after another, and scattering it on the ground. "If Molly was stabbed the blade would have come out cleaner than that – you don't get massive coatings of blood on a knife that's pulled from a wound; the pulling wipes off the blood until you just have smears. Mistake number one. Mistake number two: The knife had other matching fingerprints underneath it – not as clear because they were made by putty, but still visible. They matched the thumb print and Macfarlane's. So he had the knife in his hand before his hands were covered in blood, so far, so obvious. But who stabs someone, then puts the knife down, then dips only their thumb into the blood from the wound, picks up the knife and presses the blooded thumb into the handle?"

"So it's a plant?"

"Has to be."

"By who?"

"Who do you think?" He turned to look at me. "Who's the one untouchable person in this whole charade?"

Suddenly he stopped dumping clods of earth onto the paving and gave a cry of triumph. In his hand he held a roughly cut piece of putty.

"Look at that!" he exclaimed, thrusting it under my nose. I looked, and saw the unmistakable outline of a thumb print indented into one side. And the thumb print was stained with blood.

"Oooooh…" Sherlock whispered. "That's vindictive. Vindictive and brilliant."

"So Molly's alive?"

Sherlock looked at me, eyes blazing. "Quite possibly," he answered. "We have to get the blood tested to find out if it's Molly's blood. If it is, that proves nothing except for the fact that she was here during or just after the time that Macfarlane was repairing the windows. We need to search the house," and cradling the piece of putty in his hand, he jumped up and started briskly back to the house, leaving scattered shrubs, roots and compost all over the path.

"Sorry we took so – " I broke off and Sherlock stopped in surprise. The situation in the kitchen had altered dramatically in our absence. Lestrade was standing over Greenwood, who was handcuffed to the cooker. Greenwood had broken out in sweat and was breathing hard, staring at the floor and grinding his teeth in frustration.

"Kinky," commented Sherlock, eyes flicking between Lestrade and Greenwood.

"Tried to make a run for it," Lestrade explained. "He got all edgy once you left. Then he kept going to the window to and looking out, and shortly after that he rushed through the door. I caught him in the hall."

"Well, you have your talents." For a brief second Lestrade radiated pride, then realised the insult disguised under the complement, and restrained himself from protesting.

"He won't answer any questions."

"Doesn't need to." Sherlock handed Lestrade the piece of putty. I could see from Lestrade's face as he examined it, that he knew what it meant.

"Search the house?" And in a rare moment of mutual agreement, Sherlock nodded.

Lestrade stayed with Greenwood in the kitchen, while Sherlock conducted a thorough investigation of every room in the house. Each room was paced out, each wall was tapped, the workings of each window were carefully examined, each cupboard opened and all the walls of that tapped, and the book cases had all the books pulled from them and were shaken violently. The chimneys of the two open fires were also carefully scrutinised, and in each room Sherlock would drop down onto his hands and knees and examine every inch of the carpet. But there was no tell-tale hyperventilating – just absolute stillness and concentration.

He was still in the dark. I remembered something Sherlock had said on a previous case, about DNA analysis being all very fine and good, but if we weren't careful the old-school methods of detection would die out and we would suffer for it. Watching him examine this room, having already tested the DNA and come up with nothing new or useful, I realised just how true this was.

It wasn't until we were upstairs, having examined the landing and all the bedrooms, that Sherlock suddenly leaned against a wall and broke into a wide smile. "What have you found?" I asked him.

He indicated the hallway. "The first floor. Six feet shorter than the ground floor."

"And that has to mean…" I said, cottoning on, and Sherlock nodded, knowing what I was about to say. "So which wall?"

Sherlock wandered back along the landing to the bedroom at one end. It had a window on the end wall. "Not this one," he said, and jogged back down the landing to the second, unused bedroom. There was a film of dust on the floor that was broken only by our footsteps and some foreign ones that looked like boots. "Promisinger and promisinger," quipped Sherlock, and began knocking gently on every inch of the wooden wall. It was just under half of the way along that he suddenly stiffened, then gave three quick knocks, and then another three a few inches to the right. Then, tracing the hollow frame by sound, he knocked all round the edge of it. It was a door approximately five foot tall and four foot wide. "There's gotta be a way in," he muttered. Then his gaze fell on the edge of the carpet against the wall. It dipped down. I followed his gaze up, and saw a hinge system concealed by shadows and wall paper.

"Molly?" Sherlock put his ear to the wall and listened intently. He shook his head and dropped to his knees. Even with his thin, spidery fingers, it took a good few seconds to push them into the tiny space, and then to wrench until, with a juddering resistance, a section of the wall began to swing upwards and outwards, revealing a tiny, wooden, attic-like room. He stood up, eyes wide with expectancy, and together we surveyed our find.

It was about six by six feet, stuffy, dark, strewn with objects, deserted and smelled strongly of solvents. Sherlock squatted down once more, and examined each object in turn. There was a cloth handkerchief, an open box of matches, an unlabelled empty glass bottle which he sniffed with some puzzlement, a hypodermic syringe, and a kitchen knife with tatters of skin on the blade. A tub of terpentine in the corner was the source of the smell. Sherlock cocked his head at this, staring at it like a peg that would not fit neatly into any hole. Then a second later he gave a sharp intake of breath, and his face contorted. I joined him by the tub, and soon saw why. Lying at the bottom was a crumpled white blouse – Molly's blouse.