The Plague Court Murders Sir Henry Merrivale Series, Book 1.

THE FIRST SIR HENRY MERRIVALE MYSTERY. When Dean Halliday becomes convinced that the malevolent ghost of Louis Playge is haunting his family estate in London, he invites Ken Bates and Detective-Inspector Masters along to Plague Court to investigate. Arriving at night, they find his aunt and fiancée preparing to exorcise the spirit in a séance run by psychic Roger Darworth. While Darworth locks himself in a stone house behind Plague Court, the s...