‘You don’t think that Parker himself might be the man we’re after?’ I suggested.
‘It looks very like it. He was obviously listening at the door when you came out. Then Miss Ackroyd came across him later bent on entering the study. Say he tried again when she was safely out of the way. He stabbed Ackroyd, locked the door on the inside, opened the window, and got out that way, and went round to a side door which he had previously left open. How’s that?’
‘There’s only one thing against it,’ I said slowly. ‘If Ackroyd went on reading that letter as soon as I left, as he intended to do, I don’t see him continuing to sit on here and turn things over in his mind for another hour. he’d have had Parker in at once, accused him then and there, and there would have been a fine old uproar. remember, Ackroyd was a man of choleric temper.’
‘Mightn’t have had time to go on with the letter just then,’ suggested the inspector. ‘We know someone was with him at half-past nine. If that visitor turned up as soon as you left, and after he went, Miss Ackroyd came in to say goodnight – well, he wouldn’t be able to go on with the letter until close upon ten o’clock.’
‘And the telephone call?’
‘Parker sent that all right – perhaps before he thought of the locked door and open window. Then he changed his mind – or got in a panic – and decided to deny all knowledge of it. That was it, depend upon it.’
‘Ye – es,’ I said rather doubtfully.
‘Anyway, we can find out the truth about the telephone call from the exchange. If it was put through from here, I don’t see how anyone else but Parker could have sent it. depend upon it, he’s our man. But keep it dark – we don’t want to alarm him just yet, till we’ve got all the evidence. I’ll see to it he doesn’t give us the slip. To all appearances we’ll be concentrating on your mysterious stranger.’
He rose from where he had been sitting astride the chair belonging to the desk, and crossed over to the still form in the armchair.
‘The weapon ought to give us a clue,’ he remarked, looking up. ‘It’s something quite unique – a curio, I should think, by the look of it.’
He bent down, surveying the handle attentively, and I heard him give a grunt of satisfaction. Then, very gingerly, he pressed his hands down below the hilt and drew the blade out from the wound. Still carrying it so as not to touch the handle, he placed it in a wide china mug which adorned the mantelpiece.