Late, Late in the Evening

'How does that prove anything?'

'Surely, that you knew (as Mrs Collins was a figment of your brain) you would need an excuse to get away from the party at some point and had prepared yourself with one which could not be gainsaid.'

'And your second point?'

'It depends upon the first. You knew that Miss Patterson had arranged with her brother that she should take his place. You had thought that she would still be in the car when you met and it upset the plan a little when the unsuspecting Mrs Kempson invited her into the house. You managed, I expect, to speak to Miss Patterson while Amabel and her grandmother were still occupied in greeting the guests who were continuing to arrive. Miss Patterson proposed a new plan, which was that, after the pretended call was supposed to have come through, she should go into the garden at the first opportunity and that you two should hold your conclave in her car, as you had arranged.'

'Well, all right, fair enough, so far. And then?'

'I think you had a genuine call, and that it came earlier than the bogus one you had planned. I also think it was one which you did not hesitate to answer, and that, in fact, you welcomed it. You were not looking forward to your interview with Miss Patterson. You knew she would be reproachful; you thought she might be angry and even tearful, so, although you were determined to return to the party in the hope of having a lovers' meeting, however short, with Amabel Kempson-Conyers, you left it late enough to feel certain that, by the time you got back, Miss Patterson would have taken her three companions back to London and you would be spared an embarrassing interview.'

'And so?'

'You came back to find that Merle Patterson had gone out into the grounds, as arranged, but had not come back. A search-party was organised, her body was found and there was no doubt that she had been murdered. In other words, she had kept the tryst which, because of circumstances unforeseen by you, but of which you were quick to take advantage, you had managed to avoid.'

'I didn't kill her. I swear I didn't. I mean, you don't kill girls because they are prepared to make nuisances of themselves.'

'No? Perhaps you are not as well acquainted with the records of criminal behaviour as I am. Girls and women have been murdered simply because they were in the way. Have you heard of Emily Kaye?-of Ellen Warder?-of Harriet Staunton?-of Mrs Armstrong?-of Belle Elmore, as Mrs Crippen called herself professionally? I could go on. Shall I do so?'

'But Merle wasn't in my way! I had finished with her and she knew it. I admit I was a bit of a heel where she was concerned. She told me so in letters, anyway. I also admit I never intended to meet her in the grounds that night. I had nothing to say to her. The call I was planning to receive was just a myth, as you say. I intended to leave the house and drive off. I usually ride a horse in the village, but I use Doctor Matters' car at times and always after dark. Anyway, any double-cross act I'd planned with Merle proved unnecessary. A genuine call came through and I made the most of it.'

'Ah, yes, the genuine call. Tell me about that.'

'It came from Doctor Matters. I shouldn't criticise him to outsiders, I suppose, but he really is the most frightful old ass and to my mind completely gaga. He rang up to say that as I'd borrowed the car I was to go at once to the Pratts' house-he gave me the address-and tell them he'd given a wrong prescription and that if they'd already been to the chemist with it, Mrs Pratt was on no account to touch the stuff, but to bring it to the surgery next morning.'

'And this errand took you out of the party at an early stage in the proceedings?'

'Yes. I went off at once, of course. You can't play about with dangerous drugs.'

'And you were absent for nearly four hours?'

'Well, not as long as that.'

'Doctor Tassall, I refuse to credit your story. For one thing, Doctor Matters does his own dispensing. He does not issue prescriptions to be handed in at chemists' shops. Furthermore, it could not possibly have taken you all that time to perform such an errand. Doctor Matters' practice would have to extend to the other side of the County if it had. For your own sake, tell me the truth. I will be plain with you. If I could believe that you had any reason for disposing of Mr Ward, I would subscribe to your immediate arrest, but, so far as I know, you had no motive for that. All the same, you did have a motive for murdering Miss Patterson and doctors have committed murder before this. Come, now. For all we know at present, there may be two murderers in this village and there is nothing, so far, to show that you are not one of them.'

He shrugged his shoulders and decided to make the best of it.

'Oh, well, if you must have it,' he said, 'as I say, I never intended to meet Merle for a showdown. It couldn't do any good. I'd arranged with one of the chaps at the medical school to call me. I'd bought those lizard costumes from him, so I knew he'd oblige me. I had a few dances with Amabel under the disapproving eye of Mrs Kempson, then the chap's call came through. It was an invitation to join a gang of students in a rather low pub in the town. We had a few drinks and then I went back to the chap's room with two or three of the others and we played cards and had a few more drinks until I realised that Merle must have given up and gone home. The Kempson and Conyers tribe would be in bed, I thought, and a clod aimed at Amabel's window would bring her to the front door.'

'Instead of which, you found yourself pulled in to assist in the search for Miss Patterson. I cannot understand why you did not come out with this story at the beginning. Surely you realised that it gave you an alibi for the time of Miss Patterson's death?'

'I didn't realise at first that I needed an alibi. I'd committed myself to this story about being called out to a maternity case and I thought Amabel and her people, especially Mrs Kempson, would take a very dim view if they knew I'd left the birthday party to go on a toot with the lads. I couldn't have let Amabel know, either, that I'd agreed to a tete-a-tete with Merle out in the grounds. You know what girls are. She'd have thought it was-she'd have thought I was double-crossing her, and that would have been the end of everything.'

I felt that I had the truth from him at last. It remained to check his alibi and this I have done. There is no doubt in my mind that, whatever happened in the case of Mr Ward, young Doctor Tassall had no part in the murder of Merle Patterson unless the medical evidence respecting the time of her death was hopelessly out.

This left me with one obvious suspect, but there were difficulties. Only if we could prove that Nigel