“The next thing is to mark the exact place in the pond where he drops⁠—whatever he drops.”

“So that we can fish it out again.”

“If we can see what it is, we shan’t want to. The police can have a go at it tomorrow. But if it’s something we can’t identify from a distance, then we must try and get it out. To see whether it’s worth telling the police about.”

“Y-yes,” said Bill, wrinkling his forehead. “Of course, the trouble with water is that one bit of it looks pretty much like the next bit. I don’t know if that had occurred to you.”

“It had,” smiled Antony. “Let’s come and have a look at it.”

They walked to the edge of the copse, and lay down there in silence, looking at the pond beneath them.

“See anything?” said Antony at last.