Joseph Losey - Royal Avenue, London, UK - Blue Plaques on Waymarking.com

The IMDB website has an article about Joseph Losey that tells us:

Belonging to an important family clan in Wisconsin, Joseph Losey studied philosophy but was always interested in theater and thus worked together with Bertolt Brecht. After directing some shorts for MGM, he made his first important film, The Boy with Green Hair (1948), for RKO. While he was filming The Prowler (1951) in Italy he was summoned to testify before the House Un-American Activities Committee, the congressional committee charged with "rooting out" Communist "subversion" in the motion picture industry. Unwilling to subject himself to the committee's well-known intimidation tactics, Losey decided to seek exile in Great Britain. In the following years he used a pseudonym--"Joseph Walton"--for his films, which were of minor quality. He regained his prestige with the thrillers Blind Date (1959), The Criminal (1960) and Eve (1962). From that point on his films varied between top-quality work like Accident (1967) and much lower-quality projects such as Modesty Blaise (1966), which was a box-office success, and Galileo (1975), which wasn't.