Charlotte Rampling is about to celebrate her marriage when her husband decides to remember a “lost love” in the drama “45 Years”.
Kate Mercer (Charlotte Rampling) is about to throw a party to celebrate her and her husband Geoff’s (Tom Courtenay) 45th wedding anniversary. They are working together on the menu, who to invite and what songs to play. That was until Geoff got a mysterious letter during breakfast that brought back memories of his last girlfriend.
Geoff and Kate have been married half their lives, but Geoff begins to withdraw and starts acting peculiar. Geoff starts smoking and disappears into town on his own early in the morning. He also stops helping plan the anniversary party. Kate tries to follow him but loses Geoff in town. She returns and begins looking around the attic at the house. Kate finds that Geoff has been revisiting his prior relationship with old home movies.