When a rare Blue Moon upsets the magical balance in the city, Detective Kate Prospero and her Magical Enforcement colleagues pitch in to help Babylon PD keep the peace. Between potions going haywire and everyone's emotions running high, every cop in the city is on edge. But the moon's impact is especially strong for Kate who's wrestling with guilt over falling off the magic wagon.
After a rogue wizard steals dangerous potions from the local covens, Kate worries their suspect is building a dirty magic bomb. Her team must find the anarchist rogue before the covens catch him, and make sure they defuse the bomb before the Blue Moon deadline. Failure is never an option, but success will require Kate to come clean about her secrets.