Central Park Murder (Richard Diamond): old-time radio detective

Original Airdate: Aug. 20, 1949
Richard Diamond, Private Detective is an American detective drama, created by Blake Edwards, which aired on radio from 1949 to 1953, and on television from 1957 to 1960.
Dick Powell starred in the Richard Diamond, Private Detective radio series as a wisecracking, former police officer turned private detective. Episodes typically open with a phone call between Rick and his girlfriend Helen which quickly gets cut off as a client visits the cash-strapped Diamond's office and reluctantly agrees to his steep fee of $100 a day plus expenses. Diamond also takes on cases at the behest of his friend and former partner, Lt. Walter Levinson. Diamond often suffers a blow to the head in his sleuthing pursuits. Most episodes end with Diamond at the piano, singing a standard, popular song, or show-tune from Powell's repertoire to his girlfriend, Helen Asher, in her penthouse at 975 Park Avenue.
Levinson was played variously by Ed Begley, Arthur Q. Bryan, Ted DeCorsia and Alan Reed. Helen was played by Virginia Gregg and others. Another regular cast member included Wilms Herbert as Walt's bumbling sergeant, Otis, who also "doubled" on the show as Helen's butler, Francis.
Many of the shows were either written or directed by Edwards. Its theme, "Leave It to Love", was whistled by Powell at the beginning of each episode.