Earth Kills
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.
More from Season 1
Episode 1
Pilot
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.
Episode 2
Earth Skills
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.
Episode 4
Murphy's Law
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.
Episode 5
Twilight's Last Gleaming
A plan to contact the Ark is put in motion after Raven crash lands on Earth. Meanwhile, Abby exposes Kane's plan to reduce the population of the Ark.
Episode 6
His Sister's Keeper
Bellamy, Finn and Jasper head into Grounder territory to search for Octavia, as flashbacks show the siblings' difficult childhood on the Ark. Meanwhile, Raven finds out about Clarke and Finn.
Episode 7
Contents Under Pressure
While Bellamy tortures the Grounder, Raven and Clarke make contact with the Ark and ask Abby to help them save Finn. On the Ark, Kane deals with his guilt, and Jaha surprises the council with a shocking revelation.
