What's the connection between Star Trek and Happy Days? There are several: Anson Williams, who played Potsie on Happy Days, later directed two episodes of Star Trek: Deep Space Nine and four episodes of Voyager. Don Most, who played Ralph Malph on Happy Days, guest-starred in a Voyager two-parter.
Also, though it cannot be 10,000% proven, it's thought that Robin Williams' Mork costume, which he first wore during a guest appearance on Happy Days, and then later on Mork & Mindy, was created using the costume that Phillip Pine wore during his guest spot as Col. Green in Star Trek: The Original Series episode "The Savage Curtain." And, as many Star Trek: The Next Generation fans know, Robin Williams -- a major Trek fan -- almost guest-starred on The Next Generation.
Delving into more detail, Anson Williams directed more than 150 episodes of nearly 40 different shows, as well as several made-for-television movies. His credits spanned from L.A. Law, Xena: Warrior Princess, and Baywatch to SeaQuest, Lizzie McGuire, and The Secret Life of the American Teenager. His work on the visual effects-heavy SeaQuest caught the eye of Star Trek producer Jeri Taylor, who recruited Williams to the Star Trek universe. For Deep Space Nine, he helmed “Statistical Probabilities” and “It’s Only a Paper Moon,” and for Voyager, he directed “Real Life,” “Demon,” “The Gift,” and “Course: Oblivion.”
Most guest-starred in the well-regarded Voyager two-parter, “Workforce.” In a change of pace, he portrayed a villainous character, Dr. Kadan. Of course, most villains -- and the actors who play them -- don’t see themselves or their character as a bad guy. As so it was for Most, who told StarTrek.com in a 2017 interview, “He did what he felt needed to be done for the greater good, yet his means and methods of going about it had to be secretive and devious. That’s interesting to play, because the villains always have more levels and colors than the good guys. That’s the case most of the time.”
As for the Robin Williams connections, he did wear a Mork costume on Happy Days that very much resembled the one worn by Phillip Pine in “The Savage Curtain.” No one can absolutely, positively confirm they were the same costume. Still, they certainly look alike, and both The Original Series and Happy Days were filmed at Paramount Pictures, so the costume could conceivably have found a home in the studio’s wardrobe department and been used in any number of productions. Assorted costumes from Star Trek turned up in other shows, and costumes from assorted other shows turned up in The Original Series. By the time Williams made the leap to Mork & Mindy, it’s likely that show’s wardrobe department made several Mork costumes, but he still might have worn the one from Star Trek as well.
And, as noted, Williams almost guest-starred on The Next Generation. The role of the time-traveling con artist Berlinghoff Rasmussen in the episode “A Matter of Time” was written for him, and he reportedly wanted to do it, but the actor was shooting the movie Hook, and Max Headroom star Matt Frewer assumed the part.