Betty Boop (with dog's ears) is an entertainer in a restaurant for dogs; a waiter neglects patrons to join the floor show.

Barnacle Bill (Bimbo) is a sailor on a ship that has just come into port. As soon as he can get off the ship, he heads for Nancy Lee's (Betty Boop) house. When he gets there he begins knocking on her door. Bimbo and Betty begin singing the lyrics to a tame version of "Barnacle Bill the Sailor." The actions of the film follow along the song's storyline, with Barnacle Bimbo romancing Betty and then leaving her to go back to sea. Like many early Fleischer Studios films, this film was inspired by a popular song, a version of "Barnacle Bill" written in 1928 by Frank Luther & Carson Robison and performed by Hoagy Carmichael.

Betty is startled awake in her bed on a stormy night. She searches for the cause of the shock while she sings the song. Then, unexplainable phenomena start happening in the house. Mysterious Mose (Bimbo) appears, and sings part of the song. Bizarre cartoon creatures appear and, at first, sing and enhance Mose's "mysterious" image. Quickly, however, the antics become frightful even to Mose. The film escalates into chaos, which ends when Mose bursts, revealing him having been an automaton (full of cogs and springs) the whole time.