Tris and Four learn the truth about their society, their home and what they must do to save it all in the latest trailer for "The Divergent Series: Allegiant."

Shailene Woodley stars once again as Tris, who after the earth-shattering revelations of “Insurgent,” must escape with Four and go beyond the wall enclosing Chicago. For the first time ever, they will leave the only city and family they have ever known in order to find a peaceful solution for their embroiled city. Once outside, old discoveries are quickly rendered meaningless with the revelation of shocking new truths.

Directed by Robert Schwentke, the film also stars Theo James, Octavia Spencer, Naomi Watts, Jeff Daniels, Ray Stevenson, Zoë Kravitz, Miles Teller, Ansel Elgort, Maggie Q, Keiynan Lonsdale, Jonny Weston, Mekhi Phifer, Daniel Dae Kim, Nadia Hilker and Bill Skarsgård.

“The Divergent Series: Allegiant” opens March 18.