Kate Mercer is planning a party to celebrate her 45th wedding anniversary. One week before the celebration, however, a letter arrives for her husband Geoff, containing news that reawakens troubling and long-hidden memories. Though Kate continues to prepare for the anniversary, she becomes increasingly concerned by Geoff's preoccupation with the letter and the ensuing revelations about his past. By the time the party comes round, there may not be a marriage left to celebrate. 45 Years is an intimate, moving and beautifully restrained portrait of a marriage shaken to its core by things left unspoken.