My Favorite Martian is the third segment of the twenty-eighth episode in season 2 of Dexter's Laboratory. It first aired on February 25, 1998.
In this episode, Dexter travels to Mars as part of an assignment to find any intelligent life. However, he's unaware that Dee Dee has stowed away in his space capsule. While on Mars, Dee Dee gets covered with red dirt, prompting Dexter to think she's a real-life martian.