davywavy | The Locked Room, Part 3

A serial adventure story in five parts.

Scroll down for parts 1 & 2 if you haven't read them.

Grey, the mechanic, would have been better named brown from the oil and grime which covered him. Jenks noted that his boots were heavy and covered in oil as well, and he realised there had been no oil on Doctor Blacks’ carpet. He nodded to himself.
“I’m investigating the death of your employer, Doctor Black.”
Grey pulled himself upright from where he was tinkering with the car engine and wiped his hands on a grubby rag.
“I don’t know nuffink abaht it.”
“Yes, you would say that.”
“Ere! Whatchoo implyin’?”
“Nothing, sir, nothing. Can you simply tell me where you were earlier today when your master was murdered?”
Grey looked about, shiftily for a moment. “I was ‘ere, was’n I? I was playing with the car engine. Cook’d’ve heard me, ‘cos of it backfirin’. Sounded like gunshots, it did.”
Jenks nodded to himself. He would check that.
His attention was drawn to an odd contraption on one wall.
“What the devil is this?”
“Invention of the guv’nor. Metal detector, ‘e calls it.”
Jenks made a decision. “Do you mind if I try it out?”

A short while later, after a little instruction from Grey, Jenks was sweeping the lawns with the metal detector. As he had half expected, he soon turned up a small, but exceedingly sharp, knife in the rose beds. The blade and crosspiece were red with blood. Turning, the inspector looked at the surrounds. Blacks window was on the other side of the house, so the knife could not have been thrown there, and there were no footprints nearby. So how had the knife come to be there?
“I shall talk to Mrs White, the cook”, thought the Inspector. He had suspicions that all was not what it seemed at Dunnett Hoo.