Harry Houghton served in the Royal Navy before finding employment as an Admiralty clerk at the top-security Underwater Weapons Establishment in Portland.

In 1955 Gordon Lonsdale, a KGB intelligence office, moved to England where he worked as a company director. While living in England he established a spy ring that included Houghton, Peter Kroger and Helen Kroger. Over the next few years obtained a great deal of information on nuclear submarines and the location of secret military bases.

In 1959 Michael Goleniewski, a Polish intelligence officer, told the CIA that two Soviet agents were operating in Britain. Goleniewski was also able to identify one of these agents as working at the Underwater Weapons Establishment in Portland. This information was passed on to MI5 and eventually came to the conclusion that this agent was Houghton. By following Houghton the intelligence officers were able to discover about the activities of Ethel Gee, Lonsdale and the Krogers.

Houghton and his fellow conspirators were arrested on 7th January 1961. Harry Houghton was found guilty of spying and was sentenced to fifteen years in prison.