On February 9th 1983 Dennis Nilsen was arrested at his Muswell Hill home, after human remains had been identified as the cause of blocked drains.

Within days he had confessed to fifteen gruesome murders over a period of four years. His victims, all young homosexual men, had never been reported missing. Brian Masters, with Nilsen's full cooperation, has produced a unique study of a serial killer's mind, revealing the disturbing psychology of a mass murderer.