- 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
A major philosopher of early 22nd-century Earth, the founder of the Neo-Transcendentalists. During a chaotic period when Earth was still recovering from World War III, Dieghan advocated a return to a simpler life in which one lived in harmony with nature.