The two universes are in kind of disharmony. They’re in a fractured balance so anything that happens on one side, certainly for the duration of this season and moving forward by design, will affect the other side. - Jeff Pinker
So said the Fringe producer in response to the cataclysmic conclusion to last week's major episode.
How will events from "Immortality" play a role on this week's "6B?" Check out the official preview for the upcoming installment to get some idea. Also, click on the video below to view a clip from the episode, as Walter works and worries inside his lab.