Although Lina Bellewood has managed to escape the Institute for Benders, a place where young Shadowhunters train to become masters at bending the four elements, its secrets still haunt her. She is determined to find out how she fits into the mystery of the Elemental Marks while keeping her best friend in the dark about the worst of those secrets. Tommie Penwell is juggling his own secrets as past and present collide upon Lina's return. This careful balancing act becomes even more tricky when the remaining benders from the Institute appear at Lina and Tommie's door, ready to prepare for a battle against the Clave that may not even be coming. The crew is short on allies, trapped in the confides of the Philadelphia Institute, and can hardly get along with each other as past relationships create new tension. With four benders and more new allies, as threats approach, will these teenagers break under the pressure or rise to power?