We All Fall Down by Szabo
In River City, where magic used to thrive and is now fading, the witches who once ruled the city along with their powerful King have become all but obsolete. The city's crumbling government is now controlled primarily by the new university and hospital. But that begins to change as four particular young people's lives begin to converge.
When a corrupt police officer, an enforcer of the New City's oppressive rules, turns up dead, they are brought into each others' orbits as they uncover a deeper magical conspiracy. They do not realize that they have been selected as archetypal figures—The Maiden, the Hero, the Monster, and the Witch, intended to act out an ancient ritual that will revive the flow of magic through their world.