It's midsummer night, Litha, and the triplet witches have traversed the veil between the realms to collect their dues from the humans. Rather than the roaring bonfire and naked revellers they expect, they discover the human realm is vasty changed and only a ragtag group of rebels awaits them. Captured by the mad monk and stripped of their magic, the witches are caught in a deadly race against unseen forces to save themselves, their new acolytes, and the realms from a never-ending winter.