A teenage girl stumbles into a secret workshop at the infamous Grosholtz Candle Factory. There, beneath the suffocating scent of Americana, she discovers a collection of wax sculptures that seem just a little too life-like--a suspicion that is later confirmed when one jumps naked and screaming out of the trunk of her car and into her life.

Sixteen-year-old grim reaper Lex Bartleby tries to redeem herself among her fellow Grims by finding renegade Zara, who is indiscriminately damning souls, and stopping her once and for all.

Uncle Mort rounds up sixteen-year-old Lex, the other Junior Grims, and Grotton, the most powerful Grim of all time, for a journey to Necropolis, where only an impossible choice can save the Afterlife from destruction.