Brave New World (Fringe)

"Brave New World" is the two-part finale of the fourth season of the Fox science-fiction drama television series Fringe, and the series' 86th and 87th episodes overall. The episode, at the time of its writing and production, was created to be a possible series finale if the show was not renewed for a final season. As such, the episode not only resolves many of the plot lines introduced for the fourth season, but also several long-running plots throughout the show's run. In the episode, the Fringe division learns that Walter Bishop's old colleague, William Bell, has been in control of David Robert Jones' actions to collapse both universes in an attempt to create a new universe under his own control, and the Fringe team must make sacrifices to put an end to Bell's plans.

Both parts were co-written by Jeff Pinkner, J. H. Wyman, and Akiva Goldsman. Joe Chappelle served as director. Leonard Nimoy, though having previously stated his retirement from acting, reprised his role of Dr. William Bell. Rebecca Mader also guest starred as Jessica Holt, a person-of-interest to Fringe division.