The story opens with a flashback of Cassie Sullivan's dad, when he was a kid on a school field trip to a planetarium.

One of them, a priest, turns out to be a Silencer, a human physically enhanced by an implanted neural chip (part of the Other's "12th System") that also makes them believe they are Others.

Cassie, her younger brother Sam (called Nugget), her former high school crush Ben Parish (now using the name Zombie) and other young humans from Squad 53 are hiding at a safe house.

She screams at him about how cruel the Others' takeover has been, and the fact that Sam is forgetting his life before the invasion started, losing his traits of humanity.

The three of them return to the safe house where Evan, Cassie, Nugget and Megan (a young child they previously rescued) are waiting.

When the trio arrive, Constance grabs Nugget and puts a gun to his head, demanding that Evan be given to her so she can bring him back to Vosch.

Ringer tells them that Vosch will see that Constance's implant is offline and send a helicopter and a squad of 5th Wave troops to capture Evan and kill everyone else.

Ringer devises a plan for those in the safe house to attack the soldiers that will come to bring back the survivors from the first chopper.

When the next chopper arrives, they kill all the soldiers, capture the helicopter pilot, Major Bob, and leave a wounded Zombie behind to take Nugget and Megan to the caves.

They manipulate, commit genocide, and suppress the development of other sentient species to further their own radical deep ecologist goals.

Humans will never be able to rise to civilization again and forever stay in the stone age, thus keeping the balance of life on earth.

When this Final Wave succeeds, Vosch's reward will be a launch in an escape pod to the mothership to become an immortal consciousness.

Zombie is helping Megan and Nugget escape when he is suddenly shot in the back of the head, and everything goes white.

Cassie continuously hears an alarm warning that General Order Four will commence in five minutes and all forces are to head to designated safe areas.

Her troops want to kill Nugget, Zombie and Megan, but the Sergeant says their orders were to capture them, so they load them on the helicopter and head back to the base.

When Evan breaks her back, she knows the 12th System won't repair her quickly enough, so Ringer screams to Cassie to run.

When Evan enters the room, he only finds bits of Cassie's hair and blood in the chair, as she has torn herself out.

As he uses his super hearing to find her, entering a flooded room, where Cassie drops a live electrical wire into the water, electrocuting him.

Cassie leaves in the pod and Ringer searches her pockets for the explosive pill Vosch gave, so she can wipe out the base.

She remembers that she switched outfits with Cassie, so Ringer drags herself to Vosch's body and searches his pockets for the kill-switch that will kill all 5,000 soldiers at the base who have tracker implants.

The escape pod docks on the giant mothership, the size of Manhattan, and sees that it is filled with the high explosives that are to be dropped on Earth's cities.

Evan tells Zombie that he plans to go to as many 5th Wave military bases as he can and destroy them, calculating that for every life he takes, two will be saved.