The Sergeant jotted it down on a piece of paper. "That checks up with his own story: 9.35 p.m. Budd leaves; the North dame arrives."
"Next we have Mrs. North leaving the study at 9.45."
"Short visit," commented the Sergeant.
"She and Fletcher had a row. She admitted to that the second time I saw her. Also at 9.45 we have the unknown man entering the garden by the side gate."
"X," said the Sergeant. "That's when Mrs. North hid behind the bush?"
"Yes. X entered the study, we suppose, a minute later. That isn't important. Now, according to her first story, Mrs. North then left by way of the garden-gate. According to her second version, she remained where she was, until about 9.58, when X, accompanied by Fletcher, came out of the study, and walked down the path to the gate. She then slipped back into the study to search for her IOUs, heard Fletcher returning, and escaped through the door into the hall. She was in the hall as the clock began to strike 10.00. At 10.02, Glass, on his beat, saw a man corresponding to Mrs. North's description of X coming out of the garden-gate, and making off towards the Arden Road. He entered the garden and reached the study at 10.05 p.m., to find Fletcher dead, and no sign of his murderer to be seen. What do you make of it?"
"I don't," said the Sergeant flatly. "It's looked like a mess to me from the start. What I do say is that all this stuff of Mrs. North's isn't to be trusted. In fact, there's only one thing we've got to hold on to, which is that at 10.05 p.m. Glass found the late Ernest with his head bashed in. That at least is certain, and what's more it makes Mrs. North's evidence look a bit cock-eyed. Glass saw X leaving the premises at 10.02, which means that if he was the murderer he must have done Ernest in between 10.00 and 10.01, allowing him a minute to get out of the study and down the path to the gate."
"All right: that's probably a fair estimate."
"Well, it doesn't fit - not if you're accepting Mrs. North's evidence. According to her, it was just on 10.00 when she heard Ernest coming back to the study. You think of it, Chief: Ernest has got to have time to get into his chair behind the desk again, and start to write the letter that was found under his head. It was obvious he was taken by surprise, which means that X didn't come stampeding up the path directly behind him. He waited till Ernest was in the house: it stands to reason he must have. Once Ernest has settled down he gets to work - enters, strikes Ernest with some kind of a blunt instrument, not once, mark you! but two or three times - and then makes off. Well, if you can cram all that into two minutes you're cleverer than I am, Super, that's all. Take it this way: if Ernest saw him off the premises, he pretended to walk away, didn't he?"
"You'd think so."