What's Eating Gilbert Grape is the story of Gilbert, a man in his twenties from Endora, Iowa, who finds himself suffocated by his own family. Gilbert's father, Albert Grape, committed suicide when Gilbert was 9 years old, and since then, the family has been fragmented. Gilbert is one of six children, but the two oldest siblings (Larry and Janice) have left Endora permanently for their own reasons. Because Gilbert is the oldest son of the four children that remain, he becomes the father figure at a young age when his father hangs himself. Similarly, Amy, the oldest girl, becomes a mother-like character when their own mother no longer proves to be capable of fulfilling the role. Overcome by grief, Bonnie Grape (Momma) deals with the loss of her husband by eating constantly, finally becoming so large that she never leaves the house and needs assistance walking. This puts a strain not only on her children, who become her constant caregivers, but also on the family's finances, as Gilbert is the only one who seems to be able to hold a steady job and her eating habits have become expensive. Amy, the oldest remaining girl, is in charge of cooking and giving immediate care to Momma, while Ellen, being the youngest at 16 years old, works part-time at the local dairy bar and provides the majority of the melodrama within the family. The fourth and final sibling, Arnie, is a mentally challenged 17-year-old around whom much of the story revolves.
The planning of his eighteenth birthday party is the only thing that brings the family together, as the prognosis had been grim and Arnie was expected to "go any time now". All Momma wants is for her boy to live to see his eighteenth birthday. Gilbert, the bread-winner, the head of the family and the primary caregiver to Arnie, finds himself suffocated not only by his family duties, but also by the dull lifestyle of small-town Endora. He finds physical comfort in an affair with a married woman, Betty Carver, until he meets Becky, a free-spirited girl of fifteen who intrigues and excites him. Becky becomes Gilbert's only release, and his one object of desire, but it is Becky's insistence to help and get to know Gilbert that ultimately brings them together. What ensues is a personal journey for Gilbert that he never would have anticipated. What's Eating Gilbert Grape is a book full of humanity and wit that draws the reader into Gilbert's personal struggles and demands emotional investment. While the highly abridged movie version has enjoyed more attention and praise, Hedges' book is one that should not be missed.