Leah Blackthorn is the final 3rd of the Blackthorn Triplets: Mark, Helen and Leah Blackthorn. She is part fae and part angel, however posses magic no one has ever seen before. After being seriously injured by a greater demon during patrol with her parabatai: Isabella Herondale, James Castairs, A.K.A brother Zachariah is sent to heal her wounds, will he heal the invisible ones as well, like her broken heart or will he end up breaking her even more.