In flashbacks to one year ago on the Ark, Clarke's father discovers the Life Support problem and tells Abigail while Clark secretly listens. Clarke tells Wells, and her father is subsequently arrested by Chancellor Jaha and 'floated'. In the present, a desperate attempt to treat Jasper's wounds leads Clarke, Finn, and Wells out to search for an antibiotic seaweed. Bellamy and his crew go hunting for food and are followed by Charlotte, a troubled 13-year-old. A lethal acidic fog storm breaks, forcing Clarke, Finn, and Wells to seek shelter inside a buried car. The hunting party is caught in the same storm, and Bellamy and Charlotte manage to take refuge inside a cave. The camp is also hit, forcing the hundred to lock themselves in the dropship. While they are trapped, Clarke confronts Wells on his betrayal that resulted in her father's death, to later find out it was her mom who told the Chancellor, not Wells. Later, Charlotte takes some advice Bellamy gave her earlier, misunderstanding the meaning of his words she kills Wells.