Cassiopeia Sullivan / Cassie
Evan Walker's girlfriend, she insists that the group should stay for a while longer at the rendezvous point just in case Evan Walker survived. She and Ringer got off on the wrong foot and there is a certain amount of friction between them.
Marika / Ringer
Ringer is a blunt, straightforward teenage girl from whose perspective much of the story is told. It is revealed that before being brought to Camp Haven by Vosch, she was a refugee along with her alcoholic father, who died after his stash of alcohol ran out. She is later enhanced with The Twelfth System in another camp and kills her doctor, Claire, before escaping and hiding out in an abandoned barn with her caretaker Razor. During her stay in the camp, she and Razor developed a method of secret communication through a game they developed called "Chaseball," a mix of Chess and Baseball. Later on after the escape, when Razor questions her about her relationship with Zombie, she kisses him twice. It is also later implied that the two of them had sex.
Benjamin Thomas Parish / Zombie
He is a former Camp Haven recruit who was originally Cassie's high school crush and was later on saved by her. He is described as charming and constantly tries to coax a smile out of Ringer, which he has never managed to do before.
Sammy Sullivan / Nugget
Cassie's brother, he is saved by her from Camp Haven with Evan Walker.
Poundcake
One of those saved from Camp Haven, Poundcake later sacrifices himself to kill Grace and give the others a chance to survive.
Dumbo
Dumbo is 12 with big ears and a quick smile. He acts as the squad's medic.
Alison / Teacup
She is accidentally shot by Ringer and later captured by Vosch to save her life. Vosch keeps her alive only as a bargaining chip against Ringer as Ringer has a soft spot for her. Ringer later on escapes with her, but during their escape, Lieutenant Bob crashes the helicopter with him and Teacup on board, killing the both of them.
Alex / Razor
Razor originally does not believe Ringer about Vosch and the entire camp being the Others, but is later convinced after making his own deductions. After communicating secretly with Ringer, he escapes the camp with her and hides out with her in an abandoned barn until Vosch comes after them. He then shoots Vosch to give Ringer a chance of escaping. It is unclear whether or not he survived the confrontation with Vosch.
Vosch
Vosch is the commander of the army base where Ben ended up. He lost his wife and son to the Others. He was also the leader of the soldiers who took the children in school buses and then killed the adults, including Cassie's father. It is later revealed that Vosch is an Other; in fact, the leader of the Others. The army base that he commands, Camp Haven or Wright-Patterson, is the headquarters of the Others. It is referred to as a death camp, where they also train children as soldiers. Vosch also captures Ringer and enhances her to evolve into something beyond human. He toys with her a great deal.
Evan Walker
A former Silencer who fell in love with Cassie and turned against the Others, he survived the blast from Camp Haven but his multiple injuries cause his own Twelfth System to fail. He is nursed back to health by fellow Silencer Grace, whom he thinks he later killed, but actually leads to the rendezvous point unintentionally.
Grace
Another Other who met Evan when they were sixteen, she has no sympathy for the humans and sees them as beneath her. When she realizes that Evan has a weak spot for them, she tries to kill him. She is ruthless and willing to do whatever it takes to protect the mission of the Others.
Lieutenant Bob
He is a helicopter pilot who is forced by Razor, Ringer, and Teacup to assist in their escape from the camp. He promises to take care of Teacup, but crashes and ends up killing her.
