Fed up with her wild behavior, sixteen-year-old Lex's parents ship her off to upstate New York to live with her Uncle Mort for the summer, hoping that a few months of dirty farm work will whip her back into shape. But Uncle Mort's true occupation is much dirtier than shoveling manure. He's a Grim Reaper. And he's going to teach Lex the family business. She quickly assimilates into the peculiar world of Croak, a town populated by reapers who deliver souls from this life to the next. But Lex can't stop her desire for justice—or is it vengeance? — whenever she encounters a murder victim, craving to stop the attackers before they can strike again. Will she ditch Croak and go rogue with her reaper skills?

Sixteen-year-old Lex Bartleby is a teenage grim reaper with the bizarre ability to damn souls. That makes her pretty scary, even to fellow Grims. But after inadvertently transferring her ability to Zara, a murderous outlaw, Lex is a pariah in Croak, the little town she calls home. To escape the townspeople’s wrath, she and her friends embark on a wild road trip to DeMyse. Though this sparkling desert oasis is full of luxuries and amusements, it feels like a prison to Lex. Her best chance at escape would be to stop Zara once and for all—but how can she do that from DeMyse, where the Grims seem mysteriously oblivious to Zara’s killing spree?

Lex is a teenage Grim Reaper with the power to Damn souls, and it’s getting out of control. She’s a fugitive, on the run from the maniacal new mayor of Croak and the townspeople who want to see her pay the price for her misdeeds. Uncle Mort rounds up the Junior Grims to flee Croak once again, but this time they’re joined by Grotton, the most powerful Grim of all time. Their new mission is clear: Fix his mistakes, or the Afterlife will cease to exist, along with all the souls in it. The gang heads for Necropolis, the labyrinth-like capital city of the Grimsphere. There, they discover that the Grimsphere needs a reboot. To do that, the portals to the Afterlife must be destroyed…but even that may not be enough to fix the damage. Things go from bad to worse, and when at last the fate of the Afterlife and all the souls of the Damned hang in the balance, it falls to Lex and her friends to make one final, impossible choice.