The Sunday collection disappeared three weeks in succession.

The churchwarden insisted the box had remained locked.

Cryer examined it and found the keyhole unusually clean.

There were two boxes.

The real one was being exchanged after services for an identical empty copy.

The culprit was the churchwarden's assistant, who had commissioned the duplicate from a cabinet maker.

Cryer marked the genuine box with a hidden scratch.

The exchange occurred the following Sunday.

The assistant was waiting for him.