Gilbert Grape is a small-town young man with a lot of responsibility. Chief among his concerns are his mother, who is so overweight that she can't leave the house, and his mentally impaired younger brother, Arnie, who has a knack for finding trouble. Settled into a job at a grocery store and an ongoing affair with local woman Betty Carver, Gilbert finally has his life shaken up by the free-spirited Becky.

Haunted by memories of his father murdering a family, Arlis Sweeney prefers to keep to himself, focusing his energy on his work. One day, the traumatic past that eats away at him returns when he meets Kay Davies, a woman connected to the bloody event. Against all odds, Arlis and Kay fall in love; however, when his father, Roy, reappears in his life -- with the coldhearted Ginnie in tow -- Arlis must deal with his past demons.