Season 3

Complete listed story — includes the ending

1. Wanheda: Part One

For the past three months, Clarke has been living on her own in the woods. At a grounder trading post, Clarke sleeps with the post owner, Niylah, and is caught by a bounty hunter while leaving the next morning. At Camp Jaha, renamed Arkadia, Lincoln – unable to leave camp due to a kill order put on him by Lexa – tries to fit in with the Sky People, much to Octavia's distaste. Bellamy, with several others, goes on patrol and encounters scouts from another grounder clan called the Ice Nation. Jasper is injured, and part of the group returns to Arkadia. The rest meet up with Kane and Indra, from whom they learn there is a bounty on Clarke (who is known in the grounder circles as "Wanheda"; the Commander of Death) for the mass killings of the population of Mount Weather. They leave to search for Clarke, but the solar powered Rover ATV they are using gets trapped by a deliberately felled tree. Murphy is released from his bunker and finds Jaha and A.L.I.E. at the mansion. Murphy refuses to be a part of Jaha's mission but decides to leave the island with him when he sees that Emori is part of the boat crew.

2. Wanheda: Part Two

The attackers of the Rover ATV turn out to be fellow Ark members from Farm Station who landed separately, including Monty's mother, and under the control of Pike. Conflicts with the Ice Nation, in whose territory they landed, have reduced their numbers to 63. Pike and his group accept Kane's offer to come to Arkadia. Part of the group continues their search for Clarke, but after Bellamy is injured by the bounty hunter who has captured Clarke, the group is forced to return to base. Indra returns to the grounder city of Polis where the bounty hunter – revealed to be Prince Roan of Ice Nation – delivers Clarke to Lexa. Jaha continues his mission for A.L.I.E. While Otan distracts Jaha, Emori and (unwittingly) Murphy kill Gideon and steal a backpack containing A.L.I.E.'s portable nuclear powered hardware. When Otan returns he appears to be brainwashed, and Murphy throws the pack into the water. Emori and Murphy escape on the boat, while Jaha and Otan scramble to save the bag. A.L.I.E. reveals that no one can die in the City of Light, showing them Gideon – alive and unscarred – in the city.

3. Ye Who Enter Here

Lexa reveals to Clarke that she intends to initiate the Sky People into her Coalition. Bellamy, his girlfriend Gina, Octavia, and Raven arrive at Mount Weather with supplies for the Farm Station refugees. There, Echo, the grounder Bellamy first freed from the cages beneath the mountain, appears and speaks of an Ice Nation plot to attack the summit in Polis. Bellamy, Pike, and Octavia leave for Polis. As they reach the summit, it is revealed there is no imminent threat to those present; the "warning" was a ruse to lure them away. An assassin infiltrates Mount Weather, kills Gina, and punches in the self-destruct code. Raven and Sinclair manage to kill the assassin and get the disarm code, but Mount Weather detonates, killing all 36 members of the Farm Station; only Raven and Sinclair survive. It is revealed that Echo is working with Queen Nia of the Ice Nation, who is helped by Emerson, the last survivor of Mount Weather, in carrying out its destruction.

4. Watch the Thrones

In a fight to the death for the right to the throne, Queen Nia chooses her son Prince Roan to fight Lexa. At Arkadia, Bellamy, wracked with guilt, resigns from the guard. Monty and Jasper leave camp, and Monty confronts his grieving friend. Pike publicly confronts Kane and Abby, questioning them about the grounder army surrounding Arkadia, sent as protection by Lexa. Pike convinces Bellamy to supply him with guns and help massacre the grounder army. Lincoln, Abby, and Kane stop them at the last minute. Pike's name is then suggested for inclusion on the ballot for the upcoming Chancellor vote. Back at Polis, Lexa beats Roan but kills Nia instead of him, and pronounces Roan the king of Ice Nation. Back at Arkadia, Pike is the elected Chancellor. Pike then frees himself, his supporters, and Bellamy, and they leave to finish what they started.

5. Hakeldama

Clarke, Lexa, and other grounders from Polis discover the fallen army of grounders, slain by Pike and his followers. Indra is found wounded and claims Bellamy persuaded Pike to let her live in order to tell Lexa that the Sky People reject the newly-formed coalition. Lexa allows Clarke's return to Arkadia to tell Bellamy and the others to step down. Clarke fails to convince Bellamy, but instead induces Lexa to end the cycle of violence in hopes of peace. Murphy and Emori set up traps to steal from passersby. Murphy is caught, and one of the grounders spots the pill Jaha gave him in "Wanheda: Part One"; he demands to know where Murphy found it. After arriving in Arkadia, Jaha and A.L.I.E. set out to recruit more people into the City of Light by giving out the pills. Devastated by her chronic agony, Raven decides to take the pill, which successfully removes her pain. She then sees A.L.I.E. for the first time.

6. Bitter Harvest

When King Roan has Emerson, the last Mountain Man, delivered to Polis, Clarke must decide his fate. Ultimately, she decides to let Lexa banish him. Octavia and Kane find out Pike intends to clear a nearby grounder village and utilize their fertile soil for crops, so Octavia rides to alert the village. The village set a deadly trap for the incoming Sky People, which Octavia manages to warn Bellamy about just in time. Abby confiscates the City of Light chips from Jaha when it becomes clear he has no recollection of his son. A.L.I.E. enlists Raven's help to search the Ark for her second iteration, A.L.I.E. 2.0. They are unable to find it, which leads to the realization that it may be on the mythical 13th station, named Polaris, that got shot out of orbit before joining the rest of the Ark. Titus, the Flamekeeper, tortures Murphy for information, alongside an escape pod with two letters clearly scorched off from re-entry that, with the other marked letters, spells Polaris.

7. Thirteen

Murphy convinces Titus to tell him more about the origin of his religion, speculating that the first Commander was from the 13th station rather than born on the ground. Flashbacks to 97 years earlier reveal that after A.L.I.E. causes the nuclear apocalypse by hacking all of the world's computer launch codes, Becca – A.L.I.E.'s creator and avatar template – attempted to create A.L.I.E. 2.0 to interface more directly with humanity. When the Ark destroyed her research station Polaris, Becca injected herself with an unknown black substance while implanting the A.L.I.E. 2.0 in her neck, and traveled to Earth in an escape pod. In the present, Clarke and Lexa sleep together for the first time as they prepare to part ways in response to Lexa's decision to blockade Arkadia until Pike is removed from leadership. Titus attempts to ensure that the Sky People are destroyed by shooting Clarke and blaming Murphy for it, only he shoots Lexa accidentally. After Lexa dies, it is revealed that the A.L.I.E. 2.0 computer has been implanted in the back of her neck; Titus describes it as the spirit of the Commander.

8. Terms and Conditions

Two grounders inform Arkadia of the blockade and state that it will only be lifted if Pike is surrendered to them. In response, Pike begins to plan for war, while Kane plans to hand Pike over to the grounders. To this end, Sinclair allows himself to be arrested. He and an interned Lincoln stage an argument in lock-up, creating a distraction for Kane to capture Pike. Bellamy and other guards intercept him at the gate. Raven convinces Jasper to help her break into Pike's office to recover the confiscated chip manufacturer. Jasper, mentioning Finn, prompts a realisation that Raven has no recollection of him at all, and they leave the device where it is. As Jaha reflects on his future plans, Pike decides to sentence Kane to death for treason, forcing Bellamy and Monty to re-evaluate which side they are truly on in the ever-escalating tensions towards war.

9. Stealing Fire

In Polis, a conclave is held to decide the new Commander. Ontari, former bodyguard of Queen Nia, arrives and murders the other Nightbloods, declaring herself Commander. Titus names Clarke the new Flamekeeper and she takes the A.L.I.E. 2.0 computer chip, known to the grounders as "the Flame", to find Luna, a Nightblood friend of Lincoln. Titus kills himself to ensure Ontari cannot use him against Clarke, and Ontari swears Roan and Murphy to secrecy about the missing Flame. Bellamy goes to Octavia for help to save Kane, Lincoln, and Sinclair from execution, but is captured by Octavia and Indra. Abby, Octavia, Miller, and Harper stage an elaborate rescue, with last-minute help from Monty, whose betrayal of Pike is covered up by his mother. When Pike threatens to execute the interned grounders, Lincoln surrenders to save them, while the others escape Arkadia. Octavia watches from a distance as Pike executes Lincoln.

10. Fallen

Acting as a fake Flamekeeper, Murphy helps Ontari convince the grounders to submit to her rule; she later rapes him. Pike discovers Monty's betrayal, forcing him to flee Arkadia. Monty rejoins Kane, Octavia, and a captive Bellamy at the dropship, but Pike's men capture them, and Bellamy offers to lead them to the rest of Kane's insurgents. Instead, he leads them to the grounder blockade and hands Pike over to them. Kane goes with the grounders to Polis. A.L.I.E.'s influence spreads throughout Arkadia as more people fall under the mind-controlling influence, and Raven enlists Abby and Jasper to help her destroy the chip inside her. A.L.I.E. restores Raven's pain to torture her into submission, and then uses her to coerce Abby to take the chip. Jasper, finding the whole of Arkadia in A.L.I.E.'s thrall, manages to escape with an unconscious Raven, encountering Clarke on the way out.

11. Nevermore

Clarke and Jasper regroup with Bellamy, Octavia, Monty, and Sinclair. They decide to carry out Raven's original plan to free herself from A.L.I.E.'s control: by building an electromagnetic pulse device (EMP) from one of The 100's old wristbands and frying the chip inside her. Clarke leads the group to Niylah's trading post, where there is a salvaged bracelet. Monty and Octavia return to the dropship to retrieve additional components for the EMP, but they are attacked by Monty's mother Hannah, now under A.L.I.E.'s control. Monty fatally shoots his mother to save Octavia, and they return to Niylah's, where they are able to destroy the chip inside Raven using the EMP and Clarke cuts out its liquefied remains using Titus' Flamekeeper kit. Raven reveals to the group that the Flame is the only thing that can stop A.L.I.E.

12. Demons

Clarke's group finds Arkadia abandoned and retrieves Lincoln's journal, which contains a map to Luna's location. A mysterious masked figure attacks Harper, Miller, and his boyfriend Bryan before they can reach Arkadia and then targets Clarke, who unmasks him as Carl Emerson. Emerson kills Sinclair, and traps everyone else in the airlock planning to force Clarke to watch them suffocate. Clarke uses the Flame to kill him and saves her friends. The group holds a funeral for Lincoln and Sinclair, after which Clarke, Bellamy, Octavia, and Jasper embark on a journey to find Luna, while the others remain to use Arkadia's mainframe to hack A.L.I.E. Emori arrives in Polis and reunites with Murphy. Jaha arrives with knowledge of Ontari's deception, revealing that Emori is under A.L.I.E.'s control. Ontari has Murphy arrested, and Jaha convinces her to take a chip. With Ontari in her thrall, A.L.I.E. now has mastery of both the Sky People and the grounders.

13. Join or Die

Flashbacks depict Pike giving The 100 an Earth Skills crash-course in the two weeks prior to the events of the pilot episode. Realising the teens were being sent to the ground and failing to persuade Jaha to let him go with them, Pike beats Murphy in front of the class to incite them to fight for their survival. In the present, Kane and Pike arrive in an A.L.I.E.-controlled Polis and are taken prisoner by Ontari. While incarcerated, Pike is tortured by fellow prisoner Indra in revenge for the massacre of her people, but Murphy convinces her they must unite against A.L.I.E.'s followers. Jaha threatens Abby's life to coerce Kane into taking the chip. Clarke, Bellamy, Octavia, and Jasper arrive at the shore of a vast ocean and send a signal to Luna's people. After being drugged, they awaken aboard a disused oil rig and meet Luna of the boat people clan, who refuses to take the Flame.

14. Red Sky at Morning

At Arkadia, Harper and Monty sleep together while Raven hacks into the City of Light. She breaks through the firewalls but is blocked by the spirit of Hannah. Monty erases his mother's code, but A.L.I.E. removes herself from Arkadia before Raven can destroy her code; however, the attempt reveals that A.L.I.E. has a hidden kill switch that can end her. Murphy, Indra, and Pike escape the Polis dungeons and destroy A.L.I.E.'s core processor, but she has already migrated to the computer system on the Ark, still orbiting Earth. At the oil rig, Clarke plans to implant the Flame into Luna against her will, but is unsuccessful. Some of Luna's people return from the mainland having been taken over by A.L.I.E., and capture Jasper and Luna. After breaking free and killing her captors, Luna, knowing Clarke will stop at nothing to get her to accept the Flame, drugs Clarke and her companions, and has them returned to the mainland.

15. Perverse Instantiation - Part One

Clarke encounters Roan in the woods, and he agrees to help her infiltrate Polis to implant the Flame into Ontari as a last resort. In Arkadia, Jasper is revealed to have been put under A.L.I.E.'s control at the oil rig, and traps Monty and Raven, and takes Harper hostage. At Polis, Roan is shot by Kane and dragged away, while Clarke is captured and tortured by Abby. Murphy, Pike, and Indra rescue Bellamy and the rest of the group. Bellamy and Murphy then attempt to rescue Clarke while the others fight A.L.I.E.'s acolytes, during which Kane is almost killed in an explosion but is tackled aside by Indra, who is captured. Bellamy and Murphy arrive in time to save Clarke, but Jaha prevents them from using Ontari by inflicting a severe head wound that leaves her brain dead.

16. Perverse Instantiation - Part Two

At Arkadia, Monty rescues Harper and captures Jasper. With Ontari brain dead, Clarke frees Abby with the EMP to transfuse Ontari's Nightblood into herself so that she can use the Flame; as Clarke's friends defend her, Clarke enters the City of Light to find the kill switch though she has only a short time before A.L.I.E. absorbs the Flame and can delete the kill switch. Aided by the spirit of Lexa, summoned from the Flame by Clarke's mind, and hacking guidance from Raven, Clarke reaches the kill switch inside of a simulation of Polaris where she is greeted by the First Commander Becca and A.L.I.E. A.L.I.E. reveals that the world's abandoned nuclear power plants are melting down and releasing radiation, meaning that the Earth will be uninhabitable in the next six months and the City of Light is the only salvation. Clarke attempts to get A.L.I.E. to give people a real choice rather than force them to come, but Becca admits that A.L.I.E.'s core programming prevents such a thing from happening. Clarke proclaims that they will find another way and pulls the kill switch, destroying A.L.I.E. and freeing everyone. In the aftermath, Octavia kills Pike to avenge Lincoln's death and Clarke warns Bellamy that they haven't saved the world yet.