Following an attack on Los Angeles by terrorists, a teen girl trained with survival skills fights to protect her companions against a ruthless gang out to kill the young man she starts to fall for.

17-year-old Brooke Harper has lived a sheltered life. On a remote farm, her parents John and Mabel have taught their children how to survive in the event of a disaster. Not allowed to have social lives, Brooke feels she should be allowed to be a normal girl before she becomes an adult, which is around the corner. Her 10-year-old brother Tim hates the lifestyle even more than she does and threatens to run away. Brooke convinces him to stay. They will weather their family together.

A terrorist attack in the L.A. area destroys not only the major city, but a large swath surrounding it, including Brooke’s farm. During the attack, the youngest child, Michael, has gone missing. Mabel leads her oldest two into an underground cellar for their safety. She leaves to help John search for their son and never comes back. After things settle, Tim has a shard of glass in his leg. Brooke does her best to tend to the injury but fears it won’t be enough. He needs medical intervention. Brooke steps out to see the destruction of her land, and the bodies of her parents along with her youngest brother.

Left devastated, Brooke decides they should stay in the cellar a while to see if help arrives. Tim isn’t able to travel anyway. Two thieves attempt to steal food from the kids and die at their hands. When Tim perishes, there is nothing left to keep Brooke in the cellar. She packs supplies and heads off toward the city in hopes of finding a new life.

Grey Simpson was in L.A. at the time of the attack. He survived and does his best to continue. While looking for supplies in the shambles of a store, he is confronted by a gang led by Todd and his younger brother Sam. Sam grows bold and challenges Grey. During a struggle, Todd accidentally shoots Sam instead of Grey, who takes off with a bow and arrows he found. Sam dies in Todd’s arms, leaving Todd wanting revenge.

Brooke and Grey come across each other in the woods. She survives on her own just fine but Grey struggles. While they initially clash, there’s a playfulness between them that allows the couple to bond. They also come across a dog in their journey that Brooke names Rex. A small house seems abandoned so they decide to lay low there, only it is occupied by siblings Ellen and Peter. The foursome decides to work together. Grey is terrible with a bow, but Brooke masters it easily so she chooses it as her preferred weapon and allows Grey to use a gun.

Todd and his men catch up to them. While Brooke is off fishing and training with the bow, the others are taken prisoner. Brooke tracks them down to a campsite that night. Todd attempts to draw Brooke out. Before she succumbs, she shoots most of Todd’s boys with arrows. When she does step out of hiding, she shoots Todd with an arrow while he blasts her with a gun. Brooke wakes up back at the cabin after days, and learns the terrorist cell is dead. Help is on the way to those who need it. Brooke is happy to just stay at the cabin with her new family.