Do ghosts exist? And can they commit murder?

In telephone call to New Scotland Yard, a man calling himself Julian Kane claimed responsibility for the serial killings of a High Court Judge and a stockbroker and his wife, whose deaths the police were currently investigating.

The problem, among others, was that Julian Kane was executed for murder in 1800, some 170 years earlier, and the "ghost" on the telephone also claims responsibility for other murders for which another man is already on trial.

With the Murder Squad chasing their own shadows up blind alleys littered with false clues, the phantom killer appears to have the upper hand. Are all the killings connected? It seems unlikely, and the murder case of 1800 returns again and again to haunt the harassed detectives...