- Star Trek: The Motion Picture
- Star Trek II: The Wrath of Khan
- Star Trek III: The Search for Spock
- Star Trek IV: The Voyage Home
- Star Trek V: The Final Frontier
- Star Trek VI: The Undiscovered Country
- Star Trek Generations
Earth male and U.S.S. Voyager captain Kathryn Janeway's romantic companion, and caretaker of her dog, Molly, during her long absence. In 2375, Janeway received a letter from Mark telling her he had broken off his engagement to another woman, but the letter was actually a psychogenic creation of a gluttonous bio-plasmic organism. Later contact with Earth established that Mark had in fact broken off the engagement and since remarried.