Nine teenage girls are en route to Hawaii when their plane fails, leaving them stranded on a remote island. Among them we meet Leah, who has survived to tell their story to a pair of federal investigators. Flashbacks offer an intimate look at Leah’s pre-island life, and the taboo relationship that broke her heart.

The castaways are still reeling after a tragic event. Frustrated by everyone else's inaction, Rachel leads an expedition to the island's summit to get a lay of the land. We learn more about her career as an elite athlete, the extreme measures she's taken to succeed, and the brutal truth that she isn't sharing with the others.

A shelter-building contest turns ugly. Toni provokes strife on her team, and we'll learn in flashback that this isn't the first time her rage issues have caused devastating harm.

Assuming that rescue is imminent, the castaways let loose. The only girl who doesn't feel festive is Shelby, and a look into her past reveals why.

Starvation becomes a very real possibility for the weakened girls. Martha could spare them from that fate, but it would require a sacrifice she's not prepared to make. Flashbacks take us into her past, revealing the childhood trauma that's made it hard for Martha to grow up and rise to difficult challenges. Leah's paranoia about the island escalates to a fever pitch.

On the island, Leah feels closer than ever to proving that someone's behind their predicament. Post-rescue, fed up with the tight-lipped authorities, Leah goes searching for her own answers.