Collins laughed. “This is all your doing, Boyce. I knew how it would be. You let the whole story out to the papers, and this lunatic has been turning it over in his mind till he really believes he has done it. It’s quite a common phase. I wonder you take the trouble to go into the matter.”

“Wait a moment. You always think no one can be right but yourself. You have not heard all. A policeman has identified him. He saw him several times hanging about Leveson Square. And he has been further examined and his story hangs together. I don’t think there is any doubt that we have got the right man.”

“I am perfectly sure you haven’t,” said Collins.

Boyce turned to him. “Of course it will be a disappointment to you. I know you always like something out of the way, with mystery and special features. What do you think, Sinclair?”

“I don’t know, sir, I don’t know what to say. I don’t somehow think he is our man.”

“I am quite sure he is; he’s got to be. You understand. And I expect loyal support from my Department,” said Boyce, with decision.

“It won’t do, Boyce, old fellow,” said Collins.

“What do you mean?”

“I’ll tell you. Have you ever seen the Mikado? If so you may remember a song beginning, ‘As some day it may happen that a victim must be found.’ ”

“I am afraid I don’t follow you,” said the other coldly.