This film was Britain's first major Technicolor musical and also became the most notorious critical and box-office flop of the postwar British cinema and the largest bomb ever for its production company, the famed J. Arthur Rank Organisation.
With the condition that the film would be a hit, Kay Kendall was signed to a five-year, non-exclusive contract with the Rank Organization, and even producers Sidney Gilliat and Frank Launder offered her the role of Emmeline in The Blue Lagoon (1949) if "London Town" was a success. In the end, the film became a dud upon release, and her contract with Rank was abruptly ended, and the role of Emmeline went to Jean Simmons, who was suggested by J. Arthur Rank at the world premiere of Great Expectations (1946) and only was cast after a disastrous worldwide talent search.
Agnes de Mille accepted the job of choreographer primarily so she could go to London and be closer to her husband, who was stationed in Europe as part of the occupation force. Once she read the script, though, she hated everything about the movie and clashed with the producer every step of the way. Knowing that it would be the failure it ultimately turned out to be, she paid $5000 to have her name removed from the credits.