But Mr Clancy did not take a taxi. Carrying an overcoat over one arm, and occasionally allowing it to trail on the ground, he ambled gently through the London streets. His progress was somewhat erratic. Sometimes he moved forward at a brisk trot; sometimes he slowed down till he almost came to a stop. Once, on the very brink of crossing a road, he did come to a standstill, standing there with one foot hanging out over the curb and looking exactly like a slow-motion picture.

His direction, too, was erratic. Once he actually took so many right- angle turns that he traversed the same streets twice over.

Jane felt her spirits rise.

"You see?" she said excitedly. "He's afraid of being followed. He's trying to put us off the scent."

"Do you think so?"

"Of course. Nobody would go round in circles, otherwise."

"Oh!"

They had turned a corner rather quickly and had almost cannoned into their quarry. He was standing staring up at a butcher's shop. The shop itself was naturally closed, but it seemed to be something about the level of the first floor that was riveting Mr Clancy's attention.

He said aloud:

"Perfect. The very thing. What a piece of luck!"

He took out a little book and wrote something down very carefully. Then he started off again at a brisk pace, humming a little tune.

He was now heading definitely for Bloomsbury. Sometimes, when he turned his head, the two behind could see his lips moving.

"There is something up," said Jane. "He's in great distress of mind. He's talking to himself and he doesn't know it."

As he waited to cross by some traffic lights, Norman and Jane drew abreast.

It was quite true: Mr Clancy was talking to himself. His face looked white and strained. Norman and Jane caught a few muttered words:

"Why doesn't she speak? Why? There must be a reason."

The lights went green. As they reached the opposite pavement, Mr Clancy said:

"I see now. Of course. That's why she's got to be silenced!"

Jane pinched Norman ferociously.

Mr Clancy set off at a great pace now. The overcoat dragged hopelessly. With great strides the little author covered the ground, apparently oblivious of the two people on his track.

Finally, with disconcerting abruptness, he stopped at a house, opened the door with a key and went in.

Norman and Jane looked at each other.

"It's his own house," said Norman. "Forty-seven Cardington Square. That's the address he gave at the inquest."

"Oh, well," said Jane. "Perhaps he'll come out again by and by. And anyway, we have heard something. Somebody - a woman - is going to be silenced. And some other woman won't speak. Oh, dear, it sounds dreadfully like a detective story."

A voice came out of the darkness.

"Good evening," it said.

The owner of the voice stepped forward. A pair of magnificent mustaches showed in the lamplight.