Gossington Hall is the residence of the very conventional retired Colonel Arthur Bantry and his wife Dolly. One morning, the maid finds a dead body in the library. It is a young woman, flashily dressed and made up, with platinum blonde hair, and completely unknown to the Bantrys. She was strangled. The Colonel calls the police, and Mrs Bantry calls her old friend, Miss Marple.The police investigators include Inspector Slack and the Chief Constable of Radfordshire, Colonel Melchett. No one can identify the dead girl. Suspicion falls on a neighbour, Basil Blake, an artist who designs movie props for Lemville Studios, and whom Colonel Bantry dislikes. Blake had been dating a platinum blonde, Dinah Lee, but she is very much alive. The autopsy reveals that the girl died between 10 PM and 12 AM the previous evening, had been heavily drugged, and despite her tarty appearance, was a virgin. Dolly and Miss Marple move to the Majestic to investigate further. As Danemouth is in the next county, Glenshire, Superintendent Harper of the Glenshire police joins the investigation.