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

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

Sheidheda makes his move. A Disciple goes rogue.

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

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

Clarke and Octavia mount a desperate rescue mission as the Disciples close in on what they want.

It's a new day in Sanctum. Clarke, Octavia, Raven and Echo struggle with a new foe.

Clarke and her friends reckon with all that has happened only to find an unexpected threat looming.

After all the fighting and loss, Clarke and her friends have reached the final battle. But is humanity worthy of something greater?

Echo and Gabriel learn more about Hope and her mysterious past.

Raven faces an unexpected threat. Clarke must keep the peace among opposing factions in Sanctum.

Clarke and her friends attempt to rebuild Sanctum as a new threat rises in the woods.

Clarke and her friends find themselves on a planet that is not what it seems.

Mysterious outsiders arrive with news of Clarke's missing people.

Where in the universe is Bellamy Blake?

The red sun derails Clarke's plans.