Clarke and her friends must risk everything to fight one last battle for survival, only to glimpse an even darker threat to the last living valley on Earth.

Octavia leads her people into war. While behind enemy lines, our heroes must overcome their differences to save Wonkru from extinction.

As Clarke races to save Abby, she learns more about the trials and tribulations Wonkru faced in the bunker, and the impossible decisions they were forced to make in the dark year.

Monty strives to show Wonkru an alternative to war, and to the valley itself. Meanwhile, Abby’s health continues to deteriorate, along with McCreary’s patience.

The growing fractures in Wonkru threaten to explode once and for all. Meanwhile, in Shadow Valley, Murphy starts a fire, unleashing catastrophic results.

Clarke’s determination to protect Madi puts Bellamy in an impossible position.

Clarke and Bellamy make a startling discovery about Wonkru’s battle plans as Echo risks her friendship with Raven to complete her mission.

Kane’s attempt to prove himself useful tests Wonkru’s allegiance to Octavia. Madi faces an unexpected threat inside Wonkru, forcing Clarke to make an unlikely ally.

Octavia leads her people towards Shallow Valley against the advice of Clarke and Bellamy. Meanwhile, Kane and Abby adjust to a new set of challenges.

Our Heroes are forced to rely on the help of Shallow Valley’s dangerous new inhabitants in order to save some of their own, with surprising results.

Bellamy leads the charge investigating a potential way home. Meanwhile, Clarke and Madi deal with the new, uncertain threat to their home.

Octavia is forced to take guidance from an unlikely ally when the future of the bunker and all those inside it is jeopardized.

Clarke struggles to survive on a desolate, scorched earth while her friends in space come across a long-awaited beacon of hope.

It’s a race against the end of the world as Praimfaya arrives forcing our heroes to make impossible decisions to ensure their survival.

Jaha and Kane disagree over how to handle their grim reality. Meanwhile, Clarke leads a group to save a friend.

Clarke faces the consequences of her fateful choice.

Octavia fights in the final battle for her people’s survival, but not everyone is willing to play fair.

Jasper and Bellamy go on a quest. Meanwhile, Clarke struggles to keep the peace after word of Jaha’s discovery spreads.

After a disappointing discovery, Clarke and Abby question how far they’re willing to go. Meanwhile, Jaha finds a lead to the mysterious Second Dawn.

Clarke’s arrival on the island quickly takes a turn for the worse. Meanwhile, Bellamy tries to avoid further tragedy in Arkadia.

Clarke and Roan are forced to work together when they are tasked to deliver a dangerous but crucial asset to Abby through enemy territories.

Clarke makes a desperate plea with a former allied force in an attempt to avoid a war and ensure the survival of her people.

Continued struggles with leadership and trust in Arkadia and Polis take violent turns while Abby leads a team to a distant location hoping to find answers.

Jaha leads Clarke and Bellamy down a road to possible salvation while tensions rise in Arkadia and Polis.

The burden of leading weighs heavily upon Clarke and Bellamy when different challenges force them to determine who will live and die.

Clarke and her friends struggle with how to proceed after the fate of the world is revealed.

Our heroes begin to face the reality of their tragic situation. Everyone prepares for a final showdown.

Clarke finds hope in the most unlikely place. Meanwhile, Alie’s master plan comes together.

Clarke, Bellamy, Octavia and Jasper hit a tragic roadblock. Meanwhile, Raven and Monty make an important discovery.

Clarke is on a mission that could change everything. Meanwhile, Murphy gains insight that might prove useful in ensuring his survival. Lastly, Kane reaches a breaking point.

Jaha returns to Polis, and Murphy has a surprise encounter. Meanwhile, Octavia uncovers a clue.

Alie forces Raven’s dark side to come out, and Jasper’s anger continues to grow. Meanwhile, Octavia wrestles with her place in the world, and Monty is forced to make a split second decision.

Jaha employs a terrifying new method to convince Abby to join his cause, Kane is on a mission, and Bellamy is hit with a hard truth. Meanwhile, Monty finds himself in a precarious situation, and Jasper rushes to save one of his own.

Clarke discovers a shocking truth, and Octavia is forced to make a decision that could have devastating consequences. Meanwhile, Kane and Abby share a moment.

Kane is searching for a peaceful way to handle things but soon realizes he may be forced to resort to drastic measures. Meanwhile, Pike suspects that there may be a leak within the walls of Arkadia. Lastly, Raven has a plan and reaches out to Jasper for help.

Lexa tries to maintain peace and order within the clans, and Clarke uncovers a strange and game-changing truth. Meanwhile, a flashback takes us into the darker chapter of humanity’s past.

Clarke is torn between vengeance and mercy. Meanwhile, Kane and Octavia work together to avert a disaster, and Abby continues to worry about Raven.