4. Pete Kellett
In addition, to John Lormer and Yvonne Craig, Trekkies will also spot Pete Kellett in the Batman episode “How To Hatch A Dinosaur.” Kellett is best known for playing the primary bodyguard of Mirror Kirk (Shatner) — we only see him with our Kirk, though — in The Original Series season 2 episode “Mirror, Mirror.”
Kellett’s credits are vast when adding them up between Star Trek and the Batman television series alone. Kellett was also featured in the TOS season 3 episodes “Spock’s Brain” and “Day of the Dove,” although both of his roles (a Morg guard and a Klingon respectively) were uncredited.
Meanwhile, Kellett appeared on Batman five times! And depending on which special guest villain headlined the episodes, Kellett was either a henchman for the Joker (Romero) or a Cossack under the leadership of Egghead and Olga.