Joining his brother George in Hollywood, Tom Conway became a contract player for MGM. Conway is perhaps best known for playing “The Falcon” in ten of the series’ entries, taking over for his brother in The Falcon’s Brother, in which they both starred. This work led Conway to become a contract player with RKO Pictures. While working for the studio, Conway starred in three of Val Lewton’s horror films. In two otherwise unrelated films, Cat People (1942) and The Seventh Victim (1943), he played Dr. Louis Judd, although the character was killed in Cat People. The third Lewton film in which he starred was I Walked with a Zombie (also 1943). On radio, Conway played Sherlock Holmes during the 1946–1947 season of The New Adventures of Sherlock Holmes, following Basil Rathbone’s departure from the series. In spite of a similar vocal timbre, Conway was not as well-received as Rathbone by audiences; he only played Holmes for one season. Tom Conway’s screen career diminished in the 1950s, but he appeared in a number of British films, as well as on radio and television. In 1951, he replaced Vincent Price as star of the radio mystery series The Saint, a character which Sanders had portrayed on film a decade earlier. In 1956, the two brothers both featured (as brothers) in the film Death of a Scoundrel, though Sanders had the starring role.

From 1951–1954, Tom Conway played debonair British police detective Mark Saber, who worked in the homicide division of a large American city, in the ABC series entitled Inspector Mark Saber – Homicide Detective. In 1957, the series resumed on NBC, renamed Saber of London, with Donald Gray in the title role. Conway performed in the Alfred Hitchcock Presents episode “The Glass Eye” (1957) as Max Collodi, receiving critical praise. His final television appearance was in the Perry Mason episode, “The Case of the Simple Simon” (1964), playing the role of Guy Penrose. Conway provided his voice for Disney’s 101 Dalmatians (1961) as a quizmaster in “What’s my crime” a parody of the game show What’s my line” and as a collie who offers the dalmatians shelter in a barn, later guiding them home. His wife at the time, Queenie Leonard, voiced a cow in the barn. Despite having been financially successful in his twenty-four-year film career, Conway later struggled to make ends meet. Failing eyesight and alcoholism took their toll on him in his last years. His second wife (Leonard) divorced him in 1963 because of his drinking problem, and his brother George Sanders broke off all contact with him because of it.

Tom Conway underwent cataract surgery during the winter of 1964–65. In September 1965, he briefly returned to the headlines, having been discovered living in a $2-a-day room in a Venice, Los Angeles flophouse. Gifts, contributions and offers of aid poured in for a time. His last years were marked with hospitalizations. It was there that former sister-in-law Zsa Zsa Gabor paid Conway a visit and gave him $200. “Tip the nurses a little bit so they’ll be good to you,” she told him. The following day, the hospital called her to say that Conway had left with the $200, gone to his girlfriend’s house, and become gravely sick in her bed. It was 22 April 1967, and he died from cirrhosis of the liver at the age of 62. His funeral was held in London.