Gates McFadden was fired after first season because of a personality conflict between her and the head writer. Sexism apparently played a role in this mutual dislike.
Diane Muldaur (Pulaski) was brought in to be more of a Bones-esque character. Muldaur reportedly did not like the show too much and never intended to stay on for more than a season. Her character was declared a failed experiment and she was not offered a renewal. Which was cool with her as she went on to LA Law.
The writer McFadden had an issue with was fired after season 2 and McFadden was offered the role as Crusher once again.
What happened to her that Pulaski was off the show and Gates McFadden came back.
The basic scuttlebutt is as follows:
Gates McFadden was fired after first season because of a personality conflict between her and the head writer. Sexism apparently played a role in this mutual dislike.
Diane Muldaur (Pulaski) was brought in to be more of a Bones-esque character. Muldaur reportedly did not like the show too much and never intended to stay on for more than a season. Her character was declared a failed experiment and she was not offered a renewal. Which was cool with her as she went on to LA Law.
The writer McFadden had an issue with was fired after season 2 and McFadden was offered the role as Crusher once again.
And now you know the rest of the story.
Technically, Muldaur was never a series regular, she was billed as “Special Guest Star” in all her appearances.
Cannonically: She died on the way back to her home planet.
She fell down a turbolift shaft.
Context
She became a red shirt