‘You needn’t be frightened,’ she smiled at him; ‘I am not going to haunt the office and make your life a burden to you. But I have been thinking over our problem. I want you, Jimmy, to begin an investigation. Will you?’
‘Why certainly, if I can. What is it?’
‘If you haven’t time yourself, and I don’t expect you will have, employ a private detective. But get a good man who will do the work thoroughly.’
‘Yes, yes. But what exactly is to be done?’
‘This. The evidence seems to me overwhelming that Mr Cosgrove missed the 7.15 at King’s Cross on that Wednesday night, and went to Montrose by the 10.30. But what did he do in between?’
Daunt was puzzled.
‘I don’t understand,’ he said. ‘We have the butler’s and Miss Belcher’s evidence to corroborate Cosgrove’s own story there. I don’t see that we can reasonably doubt he did what he said.’
‘Don’t you? But I do. Probably both these people were interested. Miss Belcher we know was—she was on too friendly terms not to be. And the butler may have been well paid to tell his story. Another thing makes me doubt Miss Belcher. You remember the conversation Mr Tanner overheard between her and Mr Cosgrove in the restaurant? They mentioned an alibi. Mr Tanner thought they were talking about Austin. I don’t believe it. It was Mr Cosgrove’s own alibi they were discussing. What do you think?’
‘It’s possible, of course,’ Daunt answered slowly, ‘but I question if we can be sure of it.’ He began to think Lois had got an obsession.
‘Well, whether or not is immaterial. What matters is that Mr Cosgrove’s whereabouts after 7.30 has not been proved.’