With the new(ish) show Better Call Saul, we now have (at least) three veteran Trek actors participating in the ongoing saga of Albuquerque’s underworld. What’s interesting, is that they sprinkle the Trekverse with their appearances and character types, although, they did all play villains, of sorts.
Chuck was once in Star Trek: Voyager, character: The Clown, Episode: “The Thaw”, 1996.
Mike was once Shel-la in the episode “Battle Lines”, DS9, 1993
And Hector was once Dr. Nel Apgar aboard the Botanica Four research space station orbiting Tanuga Four in “A Matter of Perspective”, TNG, 1990.
So, you see, the criminal underworld is littered with characters that once boldly went.