Pack of Lies is a 1983 play by English writer Hugh Whitemore, itself adapted from his Act of Betrayal, an episode of the BBC anthology series Play of the Month transmitted in 1971.

Based on a true story, the plot centres on Bob and Barbara Jackson (in real life Bill and Ruth Search) and their teenage daughter Julie (in real life Gay Search, later a television reporter and newspaper journalist in the UK.) The Jacksons are friendly with their neighbours, Peter and Helen Kroger, until the couple are arrested and charged with espionage in 1961. It is revealed the Krogers actually are Morris and Lona Cohen, who during the 1950s and 1960s worked with fellow spy Gordon Lonsdale photographing and encoding as microdots various pieces of material which they then sent to their colleagues in Russia, as part of a Soviet espionage network known as the Portland Spy Ring which had penetrated Britain's Royal Navy.