Retail worker Emmett Truesdale has never fit the Southern California mold of six-pack, suntanned masculinity. Over three hundred pounds, he carries the weight of his childhood trauma and millennial ennui around his waist and in his soul. After trying every diet under the sun, he remains stuck—in his dead-end job, in love, and in his body.

Desperate for help, he enrolls in a clinical trial for a new weight loss product called Obexity. The treatment is as horrifying as the results are miraculous and as Emmett sheds pounds at superhuman speed, every part of his life improves overnight.

Unfortunately, Obexity comes with some killer side effects, including lost stretches of time and overwhelming cravings. Worse, people who were cruel to him have started disappearing and when the police warn of a cannibalistic killer on the loose, he fears that Obexity is turning him into a monster. But how can he give it up now that people are finally starting to treat him like he’s human?