Which Marx Brother appeared in a 1955 I Love Lucy episode?

Harpo Marx appeared in a 1955 I Love Lucy episode, playing himself.

The episode, also titled “Harpo Marx,” aired on May 9, 1955, during the show’s Hollywood storyline. Lucy and Ricky meet Harpo, and the episode builds toward its celebrated mirror routine, in which Lucy imitates Harpo’s movements while he silently imitates her. The sequence echoes the Marx Brothers’ visual-comedy tradition.

Harpo was the Marx Brother known for his silent screen persona, blond wig, horn, and harp. Despite that persona, he was not actually mute; his film character communicated through pantomime, props, whistles, and honks. That distinction is a common source of mistaken trivia.

The other options are Marx Brothers, but they did not make this particular I Love Lucy appearance. Groucho and Chico were the brothers most associated with verbal wordplay, while Zeppo had largely left performing by the time of the episode.