The 100 Season 1: Episode Summaries of The 100 Season 1

For a show about an apocalypse, The 100 Season 1 doesn’t actually kill many of its main characters. At the same time, the first season does a good job of making an introduction to the overall tone of the series.

The 100 Season 1

Episode 1: Pilot

Nearly a century ago, a nuclear disaster of a global scale destroyed human civilization. The 400 inhabitants of 12 orbiting space stations thought they were the only survivors. They rebuilt a new society based on the “Ark” and would only return to the surface once the radiation has subsided to a safe level. In the meantime, the entire planet was considered a nuclear exclusion zone. Leaders of the Ark include Thelonious Jaha, the Chancellor of the Council; Marcus Kane, second-in-command to Jaha; Abigail Griffin, chief medical officer; and the entire council.

There have been now three generations born in space and resources are running low. The authorities decide to send 100 delinquent teenagers from juvenile detention (known as the Delinquents’ Camp) to Earth as part of an experiment to see whether the planet has once again become inhabitable.

Among those teenagers are Clarke Griffin, daughter of Abigail Griffin; Octavia Blake, the second child of her family and therefore in violation of the Ark’s one-child policy; Bellamy Blake, her older brother; Finn Collins, whose illegal spacewalk resulted in the loss of huge volumes of the Ark’s oxygen supply; Jasper Jordan, arrested for stealing pharmaceuticals; Monty Green, his partner in crime; John Murphy, arrested for arson on the Ark; and Wells Jaha, son of Chancellor Jaha for finding out his father’s plan to send the 100 to Earth.

The 100 teenagers land on Earth to find it filled with both dangers and wonders. Clarke, Finn, Jasper, Monty, and Octavia go on a search for the Mount Weather Emergency Operations base because they have been informed there might be supplies in the facility. When Jasper is pierced in the chest, everyone comes to realize they are not alone. There are other humans, and they’re not friendly.

Back on the Ark, Chancellor Jaha has been shot and is unable to perform his duty. Marcus Kane assumes leadership while Jaha is in recovery.

Episode 2: Earth Skills

Jasper is kidnapped after the attack. His captors call themselves the “Grounders.” Bellamy, Clarke, and a few other “Arkers” are on a mission to rescue Jasper. Each of the 100 teenagers is equipped with a tracker wristband that sends vital signs to the Ark; with limited resources, Bellamy makes the others trade their wristbands for food. Now that many wristbands go offline, Abigail sends a zero-gravity mechanic named Raven to Earth.

Episode 3: Earth Kills

Bellamy leads a group to search for food, whereas Clarke is in charge of finding an antibiotic to treat Jasper’s wound. A thick acidic fog appears, forcing the search parties to find shelter. Charlotte, a 13-year-old girl who is now among Bellamy’s group, tells him she has nightmares about Chancellor Jaha executing her father for breaking a law. She silently kills Wells in retaliation.

Episode 4: Murphy’s Law

Jasper has regained some strength but is still afraid to go outside the camp. No one knows who killed Wells at this point, except Charlotte. Everybody is accusing Murphy because the murder weapon is a knife with the initials “JM” on it. Before anything bad happens, Charlotte comes forward and confesses to the murder. Clarke and Finn try to hide her as an act of mercy. However, it all goes in vain when Charlotte jumps over a cliff and kills herself.

Episode 5: Twilight’s Last Gleaming

Raven’s space pod has landed. Bellamy arrives at the landing site and immediately throws away her radio. He then confesses that he was the one who shot Chancellor Jaha. Raven tells Bellamy that Jaha is still alive. Octavia is kidnapped by a Grounder and taken to a cave. Abigail Griffin, due to her involvement in sending an unauthorized pod to Earth, is relieved from her position as a member of the council.

The 100 Season 1

Episode 6: His Sister’s Keeper

Bellamy, Jasper, and Finn lead a search party to rescue Octavia. They are attacked by a group of Grounders, leaving three Arkers to die. Clarke and Raven are looking for parts to fix the radio Bellamy threw away in the previous episode. Octavia is saved, but Finn is injured by the Grounder.

Episode 7: Contents Under Pressure

The radio is fixed. Communication between Earth and the Ark is up and running. Abigail guides Clarke in an emergency procedure to treat Finn. Bellamy captures his sister’s kidnapper and questions him. The Grounder attacked Finn with a poisonous knife, but he refuses to say anything about the antidote. Only when Octavia cuts herself with the same knife that the Grounder becomes willing to help the Arkers find the cure.

Episode 8: Day Trip

Octavia and Lincoln, the Grounder who kidnapped her, have feelings for each other. She finds an opportunity to help him escape confinement. Finn notices the prisoner leaving. Clarke and Bellamy find a warehouse of weapons; they also survive an assassination attempt by Dax, one of the Arkers. Via a video communication, Bellamy tells Chancellor Jaha about the assassination attempt and that he was coerced to shoot him by Commander Shumway. Bellamy is pardoned.

Episode 9: Unity Day

Chancellor Jaha makes a big announcement about sending an Exodus ship to Earth. Shortly after the speech, a big explosion kills several people and leaves many others injured. Diana Sydney, who replaced Abigail Griffin on the council, is behind the explosion. She knows there are not enough ships to bring everyone back to Earth, so she wants to be on the first trip. Down on Earth, Jasper spots some Grounders in the trees with weapons and a battle ensues. The first Exodus ship takes flight, but it explodes before landing.

Episode 10: I Am Become Death

Murphy tells everyone at the camp he has been captured and tortured by the Grounders. He is suffering from an illness and Clarke becomes infected; she is bleeding from her eyes. Octavia knows from Lincoln there is no cure, but the condition is not usually lethal. The disease ends up claiming the lives of 14 people. The conflict between the Arkers and the Grounders escalates.

Episode 11: The Calm

The food supply is now in ruin. People at the camp must venture out to hunt. Finn is kidnapped by Anya, one of the Grounders’ leaders. Anya wants Clarke to treat an injured little girl. If Clarke fails and the little girl dies, Finn will have to pay with his life. Bellamy once again takes a search party to locate Clarke and Finn. On the Ark, the hurried launch of the first Exodus ship had a catastrophic effect that killed at least 1500 people. Kane, Abigail, and Chancellor Jaha survived.

Episode 12: We Are Grounders (Part 1)

Clarke and Finn are captured and will be executed by the Grounders, but Lincoln comes to the rescue. They escape through a tunnel and bump into cannibalistic Reapers. Lincoln is once again the hero of the day when he lures the Reapers away, so Clarke and Finn can run for it. Murphy kills two fellow Arkers and shoots Raven before escaping the camp. The remaining people on The Ark only have 51 hours left before they run out of resources. They must land on Earth as soon as possible.

Episode 13: We Are Grounders (Part 2)

The Arkers are surrounded by the Grounders and lose the battle. Clarke orders everyone to get inside the dropship. Jasper activates the ignition system that burns everyone outside. As soon as the battle is over, a new enemy called the “Mountain Men” emerges out of nowhere. The Ark makes a successful landing on Earth, without Chancellor Jaha.

The 100 Season 1 makes for an excellent entry to the recurring themes of the series. Between the characters’ interpersonal conflicts with each other, viewers are presented with a good dose of class warfare, redemption, family feuds, and doing what it takes to survive. The 100 is an outright sci-fi show, but Season 1 never lets itself drown in the genre’s trappings.


Did you watch The 100 Season 1? Do you think it sets the show off to a good start? We’d love to hear from you.

Other things you might want to know.

How many seasons does The 100 have?

The 100 runs for 7 seasons and is comprised of 100 episodes.

Will there be Season 8?

The series creator Jason Rothenberg has said there will not be another season of The 100. In fact, he claimed to have prepared the ending since around the finale of Season 5.

What happens to Chancellor Jaha?

At the end of Season 1, his fate seems clear: he will die just as soon as the supply of oxygen runs out. However, the final episode of the first season doesn’t reveal what actually happens to him or how he dies, if he dies at all.

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