Octavia gets to know a whole new world. Meanwhile, Murphy and Emori play make believe.

Emori tries to heal Sanctum's old familial wounds while Echo, Octavia and Diyoza struggle with new ones.

Clarke confronts a new adversary. A surprising connection takes us back to the past and to the nuclear apocalypse that destroyed the Earth.

Murphy and Indra must defuse a tense situation. Old friends make new allegiances.

Sheidheda makes his move. A Disciple goes rogue.