One of the best things for an actor in the science fiction genre is that they can work the same show multiple times as different characters. With the magic that people like Michael Westmore can do with makeup, they can appear over and over and, yet, not be seen as themselves. The character takes center stage and the actor can truly stretch themselves.
In the history of Star Trek, a lot of people have played multiple roles in the same series or across the spectrum of shows, but only a few have gone on to be considered a part of the main or recurring cast. On Deep Space Nine it happened more often than any other Trek series. Here are the nine actors who first guest starred on some version of Trek and soon found themselves cast in roles that would change their lives.