Gates McFadden played Dr. Beverly Crusher onStar Trek: The Next Generation and the TNG movies but backstage issues led to McFadden's character being replaced in TNG season 2. Dr. Crusher was introduced in TNG's pilot episode, «Encounter at Farpoint,» along with her teenage son, Wesley Crusher (Wil Wheaton), and Beverly is remembered for being a consistent part of TNG's main cast. However, at the start of TNG season 2, it's revealed that Dr. Crusher transferred off the Enterprise, leaving Wesley behind.
Dr. Katherine Pulaski (Diana Muldaur) took over the job of Chief Medical Officer on the USS Enterprise-D at the start of TNG season 2, episode 1, “The Child.” Captain Jean-Luc Picard (Patrick Stewart) explained that Dr. Crusher took a promotion as the head of Starfleet Medical, although it meant leaving her teenage son Wesley alone aboard the Enterprise. Meanwhile, Dr. Pulaski was an unpopular replacement for Dr. Crusher and another switch occurred in-between seasons with Gates McFadden returning to TNG at the start of season 3, where she remained throughout the popular series' run. While Dr. Crusher’s desire to accept a promotion and advance her career explains the character’s temporary absence from the Enterprise, there are a few real-world reasons that explain why McFadden left the show and why she later came back.
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Dr. Crusher wasn't in TNG season 2 because Gates McFadden was fired by co-executive producer Maurice Hurley. Production on TNG season 1 was infamously chaotic and numerous writers quit the show during its tumultuous first year. As a result, Hurley rose to become TNG's head writer and began to put his stamp on the series as Star Trek:
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