The council decides to send 100 juvenile delinquents on a suicide mission to Earth to see if it is habitable. If the mission succeed the felonies of the 100 would be forgiven.
Glass, one of the juvenile delinquents being sent to earth, escapes the drop ship through all the commotion and tries to find her love Luke to explain to him why she was confined.
Some of the 100 die and get injured so Bellamy hunts food for the survivors with him, in the process, Thalia gets blood poisoning from a wound and the medicine Clarke needed to save her was stolen from Octavia.
Glass risks everything to be with her love Luke, and it pays off as he proposes to her out of the blue.
The Camp for the 100 is mysteriously set on fire, Octavia gets kidnapped, and Clarkes best friend dies in the fire.
Clarke and Bellamy leave the camp to look for Octavia and one of the kids at the camp gets attacked and stabbed by an arrow.