No Mutant Is an Island - S5-E4
Continuity mistake: When Jubilee starts crying, Gambit's normally-black pants are colored blue. (00:01:50)
No Mutant Is an Island - S5-E4
Continuity mistake: When Cyclops throws his uniform on the ground, it turns into a dark gray color and the yellow paraphernalia attached to it disappears. (00:03:40)
No Mutant Is an Island - S5-E4
Continuity mistake: The governor in this episode is referred to as both Governor Barker and Governor Barkley. (00:04:20 - 00:13:40)
No Mutant Is an Island - S5-E4
Audio problem: Governor Barker has the exact same voice as President Kelly. (00:04:20)
No Mutant Is an Island - S5-E4
Continuity mistake: When Cyclops first approaches the orphanage there is a tricycle on the porch near the edge of the steps. When Sarah comes out and greets him, the tricycle has disappeared. (00:04:35 - 00:05:10)
No Mutant Is an Island - S5-E4
Revealing mistake: When Sarah turns off the stove burner you can see that there is an outline of a knob that the animators either forgot to fill in or forgot to erase. (00:05:35)
No Mutant Is an Island - S5-E4
Character mistake: When Cyclops demonstrates his power to Rusty to show him that he's also a mutant, he shoots an optic blast at a building and blows a gigantic hole in its facade. While the building had the appearance of being condemned, Cyclops had no way of knowing whether there were squatters inside. He could have seriously injured or killed several people for all he knew. (00:07:35)
No Mutant Is an Island - S5-E4
Continuity mistake: When Cyclops is talking to Rusty outside the orphanage, the sign for the orphanage is much smaller than what it was shown to be in a previous scene. (00:07:35)
No Mutant Is an Island - S5-E4
Continuity mistake: When Killgrave is walking up the porch steps to reclaim Rusty, Cyclops and Sarah are standing near the edge of the porch and Killgrave nearly makes it to the top before the shot changes. When the shot changes to Sarah telling him about Rusty's trouble adjusting, Killgrave is shown to be walking a considerable distance to get to Sarah despite the fact that the he was two or three steps away from her in the previous shot. Killgrave is also shown to be walking on level ground, which means either the porch has become a lot longer off-screen or that the animators forgot he was ascending the steps. (00:08:55)
No Mutant Is an Island - S5-E4
Revealing mistake: When Rusty is being brainwashed, his eyes move down his cheeks as his head nods. (00:10:55)
No Mutant Is an Island - S5-E4
Other mistake: When Killgrave is standing in front of the projector, the projector image is cast onto his person matched color for color, except for when his own image in his true purple-skinned form appears and the image cast onto him maintains a normal flesh color. (00:11:20)
No Mutant Is an Island - S5-E4
Continuity mistake: The layout of the living room in Killgrave's house varies depending on the shot. Sometimes the half-circle couch is next to a staircase and sometimes it is not. The piano is also in a different spot on the floor each time it is shown. There are also chairs that appear and disappear throughout the scene. (00:14:55)
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)
No Mutant Is an Island - S5-E4
Continuity mistake: When Sarah resuscitates Cyclops, they are by the edge of the swimming pool. When the shot changes to Cyclops blasting through the screen door, the pool is nowhere to be seen, nor is the puddle of water that was under Cyclops in the previous shot. (00:16:10)
No Mutant Is an Island - S5-E4
Revealing mistake: When Killgrave is saying "On your knees," his eyes jump off his face. (00:18:45)
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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