Factual error: When they show the fact sheet for Dr. Bishop, his license is marked revoked, yet the license in the picture was not around when Dr. Bishop was locked up. (00:00:15)
Continuity mistake: In Episode 3-14 - 6B When Walter is using the hammer on the block of ice, the pattern that results is different when viewed from each side.
Visible crew/equipment: "Over There, Part 2": When Walter and Olivia leave the hospital in the alternate universe, William Bell pulls up in his vehicle. As he does, you can see the reflection of the crew on the metal bars in the front of the vehicle, as well as the metal side-view mirror.
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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