[2] The film was part of a trilogy based on original screen stories starring the popular literary series character.

[N 1]Old friend Cortland Grand summons private detective Nick Carter and his friend "Beeswax" Bartholomew to Washington for as meeting with Senator Monrose, who heads a committee investigating subversive groups in the U.S. Nick turns down the Senator's request to assist his committee, and flies back to New York on Cortland's personal aircraft.

Joining Nick on the flight are six beautiful models accompanied by their chaperone, detective Christine Cross, and Andrew Hendon, a polo star suspected of being a spy.

They take refuge in Cortland's New York apartment where Pat tells Nick that the spies had been threatening to kill her father, held captive in Europe.

Sending Pat to stay in a small hotel, Nick contacts Senator Monrose and realizes that Cortland is likely the leader of the fifth column spies.

[8] Film historian John Douglas Eames in The MGM Story: The Complete History Of Fifty Roaring Years (1975) described Pigeon's recurring role as sleuth Nick Carter in Sky Murder, "a 'melo'".