‘Why this. I’ve told you what we did about Cosgrove. Now you tell me what took you to Portugal.’

‘Oh, that,’ answered Tanner looking relieved. ‘It’s irregular, but I’m blessed if I care.’ He re-lit his cigar, which in his agitation he had allowed to go out, and beginning with the day of the adjourned inquest, he recounted his adventures in London and in Devon, the midnight run to Southampton, the flight to Paris, the journey to Lisbon, and finally the arrest of William Douglas. When he had finished, James Daunt was nearly as surprised and mystified as the Inspector had been a few minutes earlier.

‘ ’Pon my soul, a most extraordinary business,’ he commented. ‘There’s Austin, first suspected, then cleared, then suspected again and arrested, and now cleared again. Then there’s Cosgrove, first suspected, then cleared, and now suspected again. And now, here’s a third man mixed up in the thing. I suppose the next thing that comes out will clear Douglas!’

‘I don’t think,’ Tanner answered. ‘But what do you mean by saying Austin is now cleared again? It’s the first I’ve heard of that.’

‘Why, Cosgrove was clearly impersonating him.’

‘Not on your life,’ said Tanner with decision. ‘Mark my words, Mr Daunt, they were all there—Sir William and Austin and Cosgrove and Douglas. Every blooming one of them was there. See here,’ he continued as the other showed signs of dissent, ‘there’s evidence against every one of them. Sir William was seen there. Austin was seen too, and there’s no doubt he faked that business about the shoes. Yes, I know,’ as Daunt would have spoken, ‘his story about the shoes seems all right, and it’s very clever, but it won’t wash. He was seen there, and he was there. Then Cosgrove was there, for you’ve proved that. And lastly this man Douglas was there also, for I saw his footmarks on the boathouse floor. Yes, they were all there, and there’s some conspiracy between them.’

Though Daunt had to admit this conclusion seemed sound, it was by no means what he wished the Inspector to arrive at. His business was to clear Austin, and while the bringing in of first Cosgrove and now this man Douglas had at the time seemed all to the good, it did not help if it merely led to a conspiracy charge. But Tanner’s voice broke into his cogitations.

‘You see,’ the detective said, following on his own line of thought, ‘they were together in London. Sir William, Austin, and Cosgrove lunched together—both Austin and Cosgrove denying it, mind you—and then immediately Sir William went to see Douglas. There was some business between the four of them. There’s not a doubt of it.’

It gave Daunt a nasty shock to recall that Austin had to him also denied having seen Sir William on that Monday. If it could be proved that Austin had lied about this, as apparently it could, what reliance could be placed on any of his other statements?

There was silence for some moments, and then Daunt moved impatiently.