Jaha makes a surprising move. Clarke gets help from an unexpected source. Lincoln seeks revenge.

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

Clarke comes back to Camp Jaha with some shocking news. Finn has to face the consequences of his actions.

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

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

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

Wick and Raven are faced with a setback. Maya and Jasper witness a terrible act.

Bellamy is able to get Clarke to agree to accompany him to the drop ship. Dr. Tsing is in charge of a deadly experiment.

Lexa and Clarke get into a heated discussion during battle preparations; Bellamy races against time.

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

Lincoln and Bellamy's efforts to get into Mount Weather has some brutal consequences.

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

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.

Clarke wants answers from the President. Abby performs emergency surgery. Octavia will do anything to find Lincoln.

Clarke and Finn come face to face with a new enemy after Lincoln rescues them from Anya, while Bellamy, Raven, Octavia and Jasper deal with a vengeful Murphy. On the Ark, Jaha makes a plan to try and get to Earth.

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

Clarke begins to question Lexa's leadership decisions and Indra continues to push Octavia. Meanwhile, at Mount Weather, Jasper steps up into the role of leader, and Cage throws Maya into a life threatening situation.

Kane takes part in a mission to make peace with the Grounders. Jasper decides to take part in a risky experiment. Lincoln enters a world of pain and President Dante Wallace issues a warning.

Clarke faces the consequences of her fateful choice.

Clarke wrestles with a decision. Bellamy learns that something isn't what it seems. Meanwhile, Murphy plots to betray his former Chancellor.

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.

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

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.

Tensions are running high between Clarke and Finn. Raven finds out that Mount Weather is interfering with their communication systems.

Clarke is faced with a difficult choice and Raven helps Bellamy navigate Mount Weather as Dr. Tsing begins to harvest the 47, while Jaha and Murphy encounter a stranger on their journey to the City of Light.

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.

97 years after a nuclear war, human kind is living in space. 100 juvenile delinquents are sent down to Earth to see if the planet is habitable.

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

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

Discovering that Jasper may still be alive, Clarke, Bellamy, Finn, Wells and Murphy head out to find him. On the Ark, Abby is determined to prove Earth is habitable, and enlists a mechanic to craft an escape pod.

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

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

Three months have passed since the tragedy at Mount Weather and our heroes learn that a bounty has been put on Clarke’s head. Unbeknownst to Clarke, a team led by Bellamy and Kane journeys deep into Grounder territory to save her. Meanwhile, Murphy finds his way to the mansion and discovers a very different Jaha on a very different mission.

Where in the universe is Bellamy Blake?

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

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

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

Octavia and Diyoza make their way to the mysterious anomaly in search of the Old Man. Meanwhile, Murphy has an offer for Emori.

As a dangerous, acidic fog approaches, Clarke, Finn and Wells set out in search of a seaweed-like plant to make an antibiotic poultice for Jasper's wounds, while a vulnerable young girl follows when Bellamy takes a group out hunting for food.

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

Bellamy, Clarke and Finn try to protect Charlotte when everyone learns she killed Wells. On the Ark, Abby risks getting floated in order to give Raven the chance to launch the escape pod.

Diyoza learns more about the mysterious Children of Gabriel while Abby continues searching for a way to save Kane.

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

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

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

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 team on the ground flights to survive the threat they face on the new planet. Meanwhile, Raven must join forces with an unlikely ally to save everyone on board the Mothership.

Clarke embraces the traditions of Sanctum and tries to make amends for her past actions.

Clarke’s past catches up to her.

Bellamy and Octavia must work together to save their friends. Echo is forced to face her past.

Clarke and Finn are captured by Anya, who forces them to save the life of a victim of the explosion. Meanwhile, Raven deals with her split from Finn, and Kane fights to save the Ark and it's survivors.

Bellamy must venture into enemy territory with an unlikely companion. Meanwhile, Octavia is forced to confront her past.

Russell seeks justice. Meanwhile, Gabriel must make a difficult choice. Lastly, the Blake siblings reunite.