After an ignominious early retirement, Remington announces to his wife, Serenata, that he’s decided to run a marathon. This from a sedentary man in his 60s who’s never done a lick of exercise in his life. As Remington joins the cult of fitness that increasingly consumes the Western world, Serenata’s once-modest husband burgeons into an unbearable narcissist. Ignoring all his other obligations, he engages a saucy, sexy personal trainer named Bambi, who treats Serenata with contempt. When Remington sets his sights on the legendarily grueling triathlon, MettleMan, Serenata is sure he’ll end up injured or dead. And even if he does survive, their marriage may not.