All 17 year old Julia remembers from more than a year ago is falling through the dark with a mysterious dark-haired boy. With her foster mom and sister, she's tried in vain to recover her memories. Her falling nightmare returns each night, and she always wakes from it at 2:20 a.m.—the same time she appeared on the porch of her foster home. Then the dance goes terribly wrong and Julia learns she's somehow in the wrong time and that her falling nightmare is a glimpse into her real, and dangerous, past. Worse, she's being tracked by a group of immortals called the Timeless, who want to send her back into danger to keep the flow of history in order. Julia must avoid the trip at all costs and learn where she's truly from, because if the Timeless catch her, she will die. Things only grow more complicated when attractive but brooding Simon shows up at her school. There's something hauntingly familiar about him—so familiar, in fact, that he may have everything to do with the truth that Julia seeks. Julia finds herself growing closer and closer to him as she works to unravel her true past. But Simon has some secrets of his own, and learning the truth may be her end.

Seventeen year old Julia was once the prey of the Timeless, a group of immortals charged with keeping the flow of history in order. Now she's one of them along with her boyfriend, Simon. But her new powers mean nothing without the survival of her family, who she left behind to certain death on the Titanic. Unfortunately, rescuing them will prove far more difficult than she ever imagined. Time itself stands in her way, and it's willing to stop at no horror to prevent her from ever seeing her family again. In order to save them, Julia and Simon may have to give everything—perhaps, even, their very existence.

This is the third and final book of the Timeless Trilogy. Now mortal again, Julia and Simon must find a way to save the Titanic and their family's lives from Frank, an immortal member of the time police. Frank has gone insane with the need to destroy them and will stop at nothing to reach his goal. Even without Frank, Julia's mission will not be as easy as she thinks. There is much at stake, and the price of saving her loved ones might be too high.