Sure, Ingrid's relationship is in shambles. And sure, Emily is still haunted by her ex-husband. And maybe, the two witches aren't the best source of any sort of magical help. But their young friend, Mary approaches them anyway.
Before any of them know it, a body is found, an investigation is afoot, and this time--Ingrid and Emily are expected to be useful as they "help" the police with their case. Being the witches they are, they're just hoping to survive yet another investigation and then escape to Europe before they're inundated with corpses or convicted of a crime they simply don't have the skill set to enact.