- 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
Starfleet Admiral. Leonard was involved with the negotiations with the Vulcans following the discovery of the Klingon warrior Klaang in Broken Bow, Oklahoma. Leonard accidentally referred to the species as "Klingot."