7 Star Trek Actors Who Were Fired
2. Kirstie Alley
At the time, the inclusion of Kirstie Alley into the cast of Star Trek II looked like a costly and transparent attempt to add some much-needed mainstream star-power to a franchise film. However, Alley was legitimately a lifelong Star Trek fan, who spent her youth watching the Orignal Series and running around pretending to be Spock's daughter, so when the part came up so jumped at the chance to audition.
Despite being a hit with fans and nailing the part, by the time Star Trek III rolled around she'd been recast with Robin Curtis. Precisely why this happened though differs depending on whose version of events you're more inclined to believe but the incredibly short answer is, of course, "money".
According to the official line from Paramount at the time, Alley and her representatives had asked for 10x the fee she was paid for Star Trek II, putting her ahead of long-standing series regulars like DeForest Kelley, and after considering it decided that she didn't justify those sorts of sums.
Alley's version, which she has told herself on a number of occasions, was that when the studio approached for about reprising the role they offered her less than she was originally paid for her first outing, so she concluded that they mustn't be that interested in having her involved.
As for where the truth lies, it's probably a bit of both.