The desperate attempt to save Olivia from the death leads to the decision to enter her mind ala "Inception". In three weeks, "Fringe" will begin the story arc that builds the third season finale with "Lysergic Acid Diethylamide". The new episode airs April 15 on FOX. Speaking of what will lead up to the finale, showrunner Joel Wyman told THR, "Consistently, we've tried to have a new chapter begin at the end of the seasons. The first season was the Twin Towers and the second season was Olivia over there. This one will have the same effect that, sort of the beginning of a new understanding of the program."
The sci-fi series has just been given a full season 4 order by the network. "FOX has been supportive throughout this process, from the beginning and certainly this season, wall-to-wall. They told us they were thrilled with the show creatively, the number wasn't exactly what they would"ve hoped for but they know the audience is deep and loyal and returns, and that's valuable to them," fellow exec producer Jeff Pinkner said.
He admitted that they have had a general idea of what season 4 will bring but said, "We don't have all the episodes written but we have the framework of a plan for the next series."
source: aceshowbiz