As Devin's leg worsens, Sara faces a terrifying choice. Brigham Young makes Bridger an offer. Abish delivers a stark warning to the Shoshone.

Following a lead, Jacob joins a bounty hunter's search. Brigham Young rides into Fort Bridger. Sara, Devin and Isaac come face-to-face with evil.

Red Feather vows to fight, Jacob acts on his suspicions and Abish receives shocking news. En route to Crooks Springs, the elements intensify.

Ignoring the danger, Isaac sets out to rescue Sara. Jacob's search for Abish comes to an end. Bridger celebrates before saying good-bye.

A frightening encounter takes Sara's party by surprise. A deeply wounded Jacob forms a posse to find Abish. Isaac reconnects with his past.

At a desolate outpost, Sara and her son Devin forge new connections while searching for a guide to help them navigate treacherous trails further west.