While Kate was busy preparing for her 45th wedding anniversary, her husband Geoff suddenly received a message that brought his thoughts back to the past. The body of his girlfriend who died in an accident in the Swiss Alps 50 years ago was found. Both Kate and Jeff were shocked but unable to communicate each other's hidden uneasiness. Jeff enclosed himself in a world of memories, while Kate tried to suppress her jealousy and anxiety. she also needed to concentrate on preparing for the party, arranging music, menus and things like that. On the face of it, it seems to be business as usual, but the camera keenly captures the process from harmonious coexistence to imbalance. Whether having breakfast with Jeff or walking alone in town, Kate feels more like a stranger. The couple in the 45th Anniversary are seized by unexpected emotions and are forced to face their unfamiliar feelings, and in the process, their good times seem to be gone forever. After 45 years of living together, which emotion will prevail on their wedding anniversary?