Continuity mistake: On the park bench, while talking to Peter, Olivia's hair moves back and forth over her right shoulder. (00:32:40)
Continuity mistake: At the beginning of the episode, when Christopher is putting Loraine in the car, her stomach changes from bulging outward to flat and normal in one shot.
Answer: In the time line of Season 4, William Bell is trying to destroy both universes to create a new one, and he needs Olivia to power the collapse. So he helped her escape. But the real question is, if not in search of Peter, why Olivia has to travel to the alternate universe to be captured and replaced?
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