Retiree Tony Webster (Jim Broadbent) suddenly receives a letter from Sarah (Emily Mortimer), a woman he knew long ago. In it, he discovers Sarah has died and intended to leave him a diary in her will. That diary was written by his college best friend, Adrian (Joe Alwyn), who took his own life years before.

However, Tony discovers that the diary is now in the hands of Sarah's daughter, Veronica (Charlotte Rampling), who also happens to be his former flame from university. He seeks her out, and through their long overdue reunion and the many secrets uncovered from the diary, Tony gains a new perspective on his past, present, and future.

Based Julian Barnes' bestselling novel of the same name.