No Mutant Is an Island - S5-E4
Plot hole: When Killgrave's bodyguard dumps Cyclops face down in the pool and leaves him for dead, it is night time. When Sarah is shown to have successfully resuscitated Cyclops, it is broad daylight. If Cyclops had been floating face down in the pool for several hours then he would surely be dead. No amount of CPR would have brought him back. (00:15:45)
Answer: Chris Potter, the original Gambit voice actor, did indeed quit the role in the 4th season. His last episode was The Phalanx Covenant Part 1 so it seems reasonable that Fox would limit the use of the character even though it was recast. It doesn't appear that Potter left the role due to animosity, he stated in an interview that he wished to play Gambit in the first live action X-Men film.
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