Philip Harbinger may or may not have killed his wife. The police believe he is guilty, but would like to get a formal confession out of him to save tedious paperwork. He is held in an old courthouse in London, and whilst exercising in the yard, he hears a voice in his head that apparently comes from the wall, the witness to 300 hundred years of tortured souls in the ancient building. The dialogue between Philip and the wall act as a counterpoint to the different techniques the police use to obtain his confession.