The language of diet ads is promising and familiar: Break free! Escape! Start living! These words are the weapons in the war on fat. Many women are waging these battles, but end up fighting against their own bodies. Sarai Walker’s new novel Dietland tells the story of one of these women. Plum has decided that her life is not real; that her true self will be freed from the trap of her body once she loses weight. Meanwhile, a violent group of feminists called “Jennifer” is exacting vigilante justice on rapists and misogynists. It’s part thriller and part social commentary. Sarai Walker talks to Madeleine about her inspiration.