Lost in Space (original) cast and character guide: Who plays whom in the 1965 sci-fi series?

Lost in Space, the iconic science fiction series, is in cultural conversation again because of actress June Lockhart's sad passing on October 23, 2025. She survived an entire century and has a lot of legacy characters under her belt. Today, the actress is mostly known to a whole generation for playing nurturing, motherly roles, like in the iconic 1965 series and Lassie.

A breakthrough for the sci-fi genre in the American TV industry, the main storyline of the series revolves around the Robinson family trying to survive in space.

"The classic cult series Lost in Space (1965-1968) features a volunteer group of space travelers who find themselves lost after a space trip designed to help the Earth relieve its population problem goes awry. On Oct. 16, 1997, a volunteer American family, made up of married scientists Dr. John Robinson (Guy Williams) and Dr. Maureen Robinson (June Lockhart), and their children, Judy (Marta Kristen), Penny (Angela Cartwright), and Will (Bill Mumy), board Jupiter 2 for a five and a half year flight to the Alpha Centauri system in order to colonize the system's third planet. Along for the ride is their pilot, Major Don West (Mark Goddard), and a life sized environmental control robot. But thanks to the traitorous efforts of Dr. Zachary Smith (Jonathan Harris), an enemy agent, the trip is sabotaged. The hopelessly lost crew, along with Dr. Smith, must fight to survive while looking for a way home."

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Lost in Space character guide:

If you are interested in watching the classic series, here are the main characters of Lost in Space:

• Professor (Lt. Colonel) John Robinson (played by Guy Williams)

Lt. Colonel/Professor John Robinson is the patriarch of the Robinson family, consisting of his wife, biochemist Dr. Maureen Robinson (June Lockhart), eldest daughter, Judy, second daughter, Penny, and youngest son Will. John is an illuminary who is an expert in both applied planetary geology and astrophysics.

• Dr. Maureen Robinson (played by June Lockhart)

Dr. Maureen engaged in cooking, working in the garden, and doing light construction. This restrictive nurturing role was, unfortunately, a product of its time. But fans to this day have stuck to her compassionate quality.

• Major Don West (played by Mark Goddard)

Don West is one of the most important characters in the classic series as he pilots Jupiter 2. His military training qualifies him to pilot the futuristic spacecraft, which is why Don is one of the key crew members.

• Judy Robinson (played by Marta Kristen)

Judy is the oldest of the Robinson children, as she is in her 20s. The show and its writers build her up as a possible romantic partner for Don, as even Major West is attracted to her.

• Penny Robinson (played by Angela Cartwright)

11-year-old Penny enjoys classical music and animals. Fans especially loved Penny's scenes with her pet chimpanzee, Debbie.

• Will Robinson (played by Bill Mumy)

The youngest Robinson is a 9-year-old computer and electronics child prodigy. Will can go toe-to-toe with the secret saboteur of the crew, Dr./Colonel Zachary Smith. The robot B-9 helps the young Robinson to uncover Smith's plans.

• Dr. (Colonel) Zachary Smith (played by Jonathan Harris)

A flight surgeon, Zachary, is the central antagonist of Lost in Space. An expert in cybernetics, his plans are frequently thwarted by Will and the robot.

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Binge all three seasons of Lost in Space on Hulu. Apart from the classic show, this story has also expanded to other media like comics and novels.

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