Trent dangled the key by its tape idly. Then: 'How do you know this is the key of that case?' he asked quickly.
'I tried it. As soon as I found it I went up and fitted it to the lock. I knew where I had left the thing. So do you, I think, Mr. Trent. Don't you?' There was a faint shade of mockery in Marlowe's voice.
'Touché,' Trent said, with a dry smile. 'I found a large empty letter-case with a burst lock lying with other odds and ends on the dressing-table in Manderson's room. Your statement is that you put it there. I could make nothing of it.' He closed his lips.
'There was no reason for hiding it,' said Marlowe. 'But to get back to my story. I burst the lock of the strap. I opened the case before one of the lamps of the car. The first thing I found in it I ought to have expected, of course, but I hadn't.' He paused and glanced at Trent.
'It was—' began Trent mechanically, and then stopped himself. 'Try not to bring me in any more, if you don't mind,' he said, meeting the other's eye. 'I have complimented you already in that document on
