‘Bob took the darts and stepped back. Then he began to blaze away with ‘em. He never so much as glanced at ‘em, I know that. He played ‘em out quick.’

‘Until the fourth one stuck into the finger?’

‘Yes,’ said Will doggedly, ‘till then.’

Alleyn was silent. Fox, notebook in hand, moved over to the window and stood looking over the roofs of Ottercombe to the sea.

‘I’ll tell you what it is,’ said Will suddenly.

‘Yes?’ asked Alleyn.

‘I reckon the poison on those darts’s a blind.’

He made this announcement with an air of defiance, and seemed to expect it would bring some sort of protest from the other two. But Alleyn took it very blandly.

‘Yes,’ he said, ‘that’s possible, of course.’

‘See what I mean?’ said Will eagerly. ‘The murderer had worked it out he’d poison Mr Watchman. He’d worked it out he’d put the stuff in his drink, first time he got a chance. Then when Bob Legge pricks him by accident, the murderer says to himself, “There’s a rare chance.” He’s got the stuff on him. He puts it in the brandy glass and afterwards, while we’re all fussing round Mr Watchman, he smears it on the dart. The brandy glass gets smashed to pieces but they find poison on the dart. That’s how I work it out. I reckon whoever did this job tried, deliberate, to fix it on Bob Legge.’

Alleyn looked steadily at him.

‘Can you give us anything to support this theory?’

Will hesitated. He looked from Alleyn to Fox, made as if to speak, and then seemed to change his mind.

‘You understand, don’t you,’ said Alleyn, ‘that I am not trying to force information. On the other hand if you do know of anything that would give colour to the theory you have yourself advanced it would be advisable to tell us about it.’

‘I know Bob Legge didn’t interfere with the dart.’

‘After it was all over and the constable looked for the dart, wasn’t it Legge who found it?’

‘Sure-ly! And that goes to show. Wouldn’t he have taken his chance to wipe the dart if he’d put poison on it?’

‘That’s well reasoned,’ said Alleyn. ‘I think he would. But your theory involves the glass. Who had an opportunity to put prussic acid in the glass?’

Will’s fair skin reddened up to the roots of his fox-coloured hair.

‘I’ve no wish to accuse anybody,’ he said. ‘I know who’s innocent and I speak up for him. There won’t be many who’ll do that. His politics are not the colour to make powerful friends for him when he’s in trouble. I know Bob Legge’s innocent but I say nothing about the guilty.’