Holly couldn't live without her husband Gerry, until the day she had to. They were the kind of young couple who could finish each other's sentences. When Gerry succumbs to a terminal illness and dies, 30-year-old Holly is set adrift, unable to pick up the pieces. But with the help of a series of letters her husband left her before he died and a little nudging from an eccentric assortment of family and friends, she learns to laugh, overcome her fears, and discover a world she never knew existed.
A young married couple, Holly and Gerry, have a joke between them: If anything ever happened to him, he'd have to write her a list or else she'd never be able to cope without him. "The List" grew to encompass advice for any eventuality, a joke all their friends shared. When Gerry's severe headache is diagnosed as brain cancer and Holly tragically loses him in a few short months, she is devastated and unmoored. She hasn't just lost her husband, she's lost her very identity. And then arrives: a package marked "The List." Gerry has Kept his promise, and inside this package are ten enveloped to be opened over a period of ten months. Each letter offers specific instructions to guide Holly through grief, and ultimately grant her permission to return to life. Of course each letter ends with P.S., I Love You.