She first appears in Morgan's first novel, The 100, and in the pilot episode of the television series, as a prisoner on a space colony charged with treason.

Clarke discovers that her parents are conducting illegal experiments on children under threat of the corrupt Vice Chancellor Rhodes.

Clarke eventually meets Sasha's father, Max, who is a leader of an underground colony underneath the ruins of Mount Weather Emergency Operations Center.

After drop ships from the Colony arrive, Vice Chancellor Rhodes attempts to take control over the community Clarke built with Bellamy and Wells on Earth.

Later, Clarke and Bellamy lead a rescue effort to save members of their community who are kidnapped by cultists who call themselves the Protectors.

Before her imprisonment, Clarke's father discovered that the Ark space station was running out of oxygen, and had an estimated 6 months' worth left.

He shared this information with Clarke and planned to reveal his findings with the larger community against the Chancellor's orders, only to have Abigail report him.

Because of her status of prisoner she was considered to be expendable by the council and was volunteered by her mother to be sent down to Earth to test the air to see if it was livable again with 99 other delinquents, including Wells, Octavia, Jasper, Monty, and Finn.

They were originally aimed for the Mount Weather complex, a quarantine zone that had food and supplies, only to find out that they landed in the forest miles away.

In the third season, Clarke returns to take a leading role in the war against A.L.I.E., the AI that caused the nuclear apocalypse that destroyed the world.

In the season finale, Clarke uses a transfusion of Nightblood from Ontari of the Grounders in order to take possession of a device known as the Flame, which is the A.L.I.E.

With 1,200 survivors in a massive fallout bunker, Clarke and several of her friends attempt to escape to the remains of the Ark in space as an alternate means of survival.

As Clarke continues to attempt to communicate with her friends without success from Shallow Valley, the only inhabitable part of Earth left, a prison transport ship arrives.

With Madi becoming the new Commander after taking the Flame, Clarke kills McCreary, the leader of the prisoners, but not before he launches the Damocles bomb at Shallow Valley as an act of scorched earth.

Along with everyone else, Clarke enters cryo sleep, only to emerge with Bellamy 125 years later, greeted by Jordan, the son of Monty and Harper.

However, the leaders of the society, the Primes, are the original mission team who keep reincarnating themselves by implanting drives holding their consciousness into new Nightblood hosts, similar to the Flame.

Though she fails, she manages to take control of one finger and use it to discreetly send Bellamy, who had since learned what happened to her, a message using Morse code that she is still alive.

After Raven discovers that the mysterious Anomaly is in fact a wormhole linking six different planets together, Clarke leads a group to search for and rescue their missing friends.

Eventually tracking the Disciples to Bardo, Clarke discovers that their leader is Bill Cadogan, the founder of the Second Dawn doomsday cult that built the bunker on Earth that Wonkru survived in, and that Bellamy is apparently dead.

In the series finale, a grief-stricken and vengeful Clarke murders Cadogan as he starts the test to determine if humanity is worthy of Transcendence or not.

I'd been living in LA for about a month and my credit card was stolen and all my money was taken – spent at Home Depot, which was great – and I was ready to pack my bags and go back to Australia because I didn't know how I was going to survive in LA any longer and then I got a call from my manager to say that an audition I'd done months ago for a film had been looked at by the producers of this TV show called The 100 and they wanted me to go in for a reading the next day.