Dawn Summers is the Key, an ancient entity given the form and memories of a normal girl. She was entrusted to the slayer, Buffy, for safekeeping against the hell-god, Glorificus. With Glory defeated, Dawn Summers believed her destiny as a destructive force in the universe was put to rest forever. Striking out on her own for the first time, Dawn is just looking for the normal life her sister always wanted.

What she finds is trouble with a capital Transdimensional portal. Fate has not forgotten the young woman and her life is thrown back into turmoil. But she's been given a helping hand in the form of a watcher, a witch, a hunter and an enigma. Her quest is clear; find the keys, avoid the enemy, discover her fate.