'Bonanza': Guest Stars You Forgot Were On The Show

Bonanza was famous for its cast of "Cartwrights," but the TV Western also featured notable guest stars across its 14 seasons. The range of guests included iconic movie stars and many up-and-coming actors who would later become A-list names. 

In this gallery, we'll look back at the guest stars you probably forgot appeared on the show — starting with Leonard Nimoy! "Spock" himself acted in a 1960 episode, before again joining Bonanza for TV movie Under Attack in 1995. His future Star Trek co-star DeForest Kelley also had several Bonanza appearances.

Ricardo Montalban also had a Bonanza appearance before he became a legendary name on Star Trek and Fantasy Island. In a 1960 Bonanza episode, the Mexican-born actor played "Matsuo," an Indian who crosses paths with "Ben" (Lorne Greene).

Yes, even Zsa Zsa Gabor had an episode on Bonanza in season 8 (1967). She played "Madame Marova," a phoney fortuneteller who convinces "Hoss" (Dan Blocker) he's a skilled violinist. Zsa Zsa was one of the three Gabor sisters, the famous Hungarian-born actresses and socialites.

In 1967, the same year Gilligan's Island concluded, actress Tina Louise saddled up on Bonanza. She played "Mary Burns" in a season 9 episode about survivors of an Indian raid. She wasn't the only former castaway to visit the Ponderosa, however.

Dawn Wells—who played "Mary Ann Summers" on Gilligan's Island—actually had two appearances on Bonanza, one before and after the iconic castaway sitcom. She played different roles in the episodes and is seen pictured here with "Adam" (Pernell Roberts).

Fittingly, Western icon Lee Marvin worked his way into a memorable Bonanza episode in season 3. In "The Crucible," he played "Kane," a villainous miner who clashes with "Adam" (Pernell Roberts). Roberts named it as one of his favourite episodes, too.

In Bonanza season 5, Marlo Thomas played a mail-order bride mistakenly sent to "Hoss." The That Girl star's role was a memorable one, as "Tai Lee" inspired a workers' rebellion on a Virginia City railroad.

Adam West is among the stars to act on Bonanza before they landed their career-defining roles. He guest starred in early Bonanza episode "The Bride," still a few years before he'd don the cape of "Batman." See his look on the Western in the bottom right corner.

Continuing the trend, West was not the only Batman TV actor to join Bonanza. "Penguin" actor Burgess Meredith is pictured here in his 1967 appearance on the NBC show. Cesar Romero, best known for playing "The Joker," likewise had a Bonanza guest spot.

Best known today as a film star and director, Dennis Hopper began his career as a TV actor. The Apocalypse Now and Easy Rider icon was frequently seen on TV Westerns in the 1950s and '60s, and he played "Dev Farnum" on Bonanza.