And Those We Left Behind - S4-E6
Continuity mistake: While beginning to take the radiation readings of the Jeep during his time jumps, Peter has a wedding ring on his finger. After cutting away and back again, the wedding ring is no longer on his finger. (00:15:15)
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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