In the novel Sleeping Murder Dr Penrose is a psychiatrist working at Saltmarsh House, a nursing home in Norfolk where Major Halliday spent the last years of his life. Gwenda Reed came to see him to seek information about Halliday who was her father.
Penrose told Gwenda that her father had an obsession or delusion that he had strangled his wife Helen Halliday, although he could not remember the act of actually killing her. Nonetheless the obsession was strong and he would not be shaken. He also believed that his wife had been administering drugs to him--thinking it was like the wives in India who drove their husbands insane with datura poisoning. He had apparently suffered often from hallucinations, with confusion of time and place. This obsession was so strong that eventually he committed suicide.
Nonetheless, Penrose was certain Halliday could not have killed Helen. Halliday was most not a paranoiac type. He had no delusions of persecution, no impulses of violence. He was a gentle, kindly, and well-controlled individual.
Penrose also handed over to Gwenda a diary which her father had kept while in the sanatorium.
There is very little description of Penrose in the text except that Gwenda Reed observed that Penrose "looked a little mad himself. He looked, for instance, much madder than the nice old lady in the drawing-room" but perhaps it was because in Gwenda's view "psychiatrists always looked a little mad".
Portrayals[]
BBC's Miss Marple[]
In the BBC 1987 adaptation of the novel, Dr Penrose is portrayed by John Ringham.