Cast of 3rd Rock from the Sun

John Lithgow portrays the character of Dick Solomon, the high commander of the alien expedition. Dick assumes the identity of a college professor and becomes fascinated with Earth and its inhabitants.

Kristen Johnston plays the role of Sally Solomon, one of the extraterrestrial crew members. Sally takes on the appearance of a tall, attractive woman and struggles to adapt to human life, often grappling with her own desires and emotions.

Jane Curtin portrays the character of Mary Albright, a professor of anthropology who becomes suspicious of the strange behavior exhibited by the Solomon family. She eventually discovers their true identities and becomes involved in their adventures.

Joseph Gordon-Levitt plays the role of Tommy Solomon, the youngest member of the Solomon family. Tommy assumes the form of a teenager and experiences the typical joys and challenges of adolescence while also trying to keep the family's true nature a secret.

French Stewart portrays the character of Harry Solomon, another extraterrestrial crew member. Harry takes on the appearance of a dim-witted and eccentric individual, often comic relief on the show due to his quirky behavior.

Simbi Khali plays the role of Nina Campbell, Mary Albright's best friend and coworker. Nina is a kind-hearted and supportive character who becomes aware of the Solomon family's secret and becomes more deeply involved in their intergalactic mission.

Wayne Knight portrays the character of Don Orville, the bumbling and somewhat oblivious police officer who frequently interacts with the Solomon family. Don provides comic relief through his constant attempts to understand the strange occurrences happening around him.