It all starts when teenager Charley Crowder is snatched out of her ordinary life by a mysterious portal. She’s deposited, naked and confused, in the middle of nowhere on what turns out to be an island not located on any map or chart. Rather than lay down and die, she struggles to survive, and after several weeks, she discovers, much to her surprise, that she’s not alone.
She’s quickly integrated into a community of fellow castaways, other teens stolen from around the world. She’s informed that the island has a name—Nil—and that the only way off is through a portal such as the one that brought her there in the first place. And while Nil, which seems to be at least partially sentient and somewhere between capricious and malevolent, has many rules for survival, the big one is this: if you don’t find your way home within a year, you die. Simple as that. Suddenly, the clock is ticking.