His many books include The Crimes, Detection and Death of Jack the Ripper, The Krays: Unfinished Business, The Official Encyclopedia of Scotland Yard, Serial Killers, and The Murder Guide to London.
After he separated from his wife (they would divorce in 1984), he resigned from his job to write a book about science, philosophy and 19th-century literature, but he lost seven years of work in a fire.
[5][6] In 1983 he returned to England and moved into a block of flats previously occupied by the Kray twins, and became a freelance writer and broadcaster, specialising in true crime.
He broadcast a weekly segment on London's LBC Radio series Leading Britain's Conversation called Murder After Midnight from 1987 to 2001, in which he detailed a famous true crime case in each episode.
[8] Former criminal profiler for the FBI John E. Douglas endorsed Fido’s hypothesis after conducting a thorough two-decade personal investigation into the Whitechapel murders.