Sam and Tusker, who have been romantic partners for two decades and share a passion for amateur astronomy, set out on an adventurous road trip through England in their campervan. Their journey takes them to the picturesque Lake District, where they plan to revisit cherished locations and reunite with friends and family.
However, their trip is tinged with sadness as Tusker has been diagnosed with early onset dementia, a condition that increasingly strains their relationship. As Tusker grapples with his illness, he finds himself struggling to write a book, unwilling to share his work with Sam. On the other hand, Sam, a gifted pianist and composer, is preparing for what he claims will be his final concert.
Their journey takes a concerning turn when, while Sam is busy shopping for essentials, Tusker ventures out to walk their dog without his mobile phone. He soon finds himself disoriented, prompting a frantic search by Sam, who eventually manages to find them both unharmed. This troubling incident leaves Sam shaken, yet he hides the extent of his worry from Tusker.
Throughout the road trip, the couple engages in light-hearted banter and gentle disagreements that showcase their deep bond. One night, they find solace at the edge of a serene lake they had once visited during the early days of their relationship, two decades prior.
Upon arriving at Sam’s sister Lily's home, where they are given accommodation in Sam's childhood room, she again suggests that they consider hiring a caregiver to alleviate some of the pressures on Sam. He steadfastly refuses, believing that it's not yet necessary. During a tranquil walk through the woods, Sam attempts to discuss the future, including necessary adjustments in their home and his decision to cease performing, but Tusker remains closed off to these conversations.
As the days unfold, friends and family gather for a surprise celebration in honor of the couple. During a chat with a friend, Sam discovers that Tusker has been struggling with his writing, a struggle he had kept hidden. Intrigued, Sam searches through Tusker’s journal and is alarmed to find the decline of Tusker’s writing skills over time. To his shock, he unearths a vial of pentobarbital and a recorded message in which Tusker explains his intention to end his life before his condition escalates.
In a rented countryside cottage, Sam confronts Tusker with this unsettling discovery and plays the farewell tape for him. A passionate and emotional argument ensues, where Sam fervently pleads with Tusker not to go through with his plan. Despite their heartfelt exchange, Tusker’s stance remains resolute. However, they reconcile the following day, sharing a tender evening together. The morning after, as Sam plays a touching melody on the piano, he expresses his acceptance of Tusker’s decision and reveals his desire to be by his side when the time comes.
In a poignant conclusion, Sam takes the stage to perform the beautiful piano piece that Tusker holds dear, embodying their enduring love amidst the heartache of their situation.
