21 Beacon Street is an American detective television series that originally aired on NBC from July 2 to September 10, 1959. Produced by Filmways, the summer replacement series consisted of 11 black-and-white 30-minute episodes starring Dennis Morgan as private investigator Dennis Chase. Other cast members included Joanna Barnes as Lola, his aide; Brian Kelly as Brian, a law school graduate; and James Maloney as Jim, a scientific and dialect specialist. The title was the Boston address of Chase, who would pass each case to the police after solving the crime.