As Lady Abbott, portrayed by Imelda Staunton, a woman steeped in elegance and tradition, grapples with the shocking revelation that her husband of 35 years, Mike Abbott, played by John Sessions, has been unfaithful with her best friend, Pamela Harper, enacted by Josie Lawrence. This unexpected betrayal sends Sandra’s life into a tailspin, prompting her to seek refuge in the unlikely setting of her estranged sister Bif's life, played by Celia Imrie, within the inner-city council estate.
Bif's bohemian lifestyle, filled with casual romances and a breezy attitude, starkly contrasts with Sandra's previously secure and predictable existence. The transition is jarring for Sandra, who struggles with her new reality. A dramatic turn of events at an Asian restaurant leads to a confrontation with the owner, forcing her into a night spent in police custody, all while she wrestles with her inner turmoil.
The following morning, Sandra receives a heart-wrenching phone call from Mike, informing her of his decision to leave their marriage for Pamela. This devastating announcement initiates a severe anxiety attack, leading Bif to rush her sister to the hospital where Timothy Spall, as Charlie Glover, helps guide them through the aftermath, encouraging Sandra to contemplate a future filled with new possibilities.
Settling into life on the estate proves difficult, and Bif encourages Sandra to join a community dance class. Here, she begins to confront her emotional barriers and rekindle memories of her past ballroom dancing, finding an unexpected friendship with Charlie, who is facing his own grief over the loss of his wife.
When Sandra’s daughter, Nicola, portrayed by Marianne Oldham, and her grandson, Luke, enter the scene, they add complexity to Sandra’s life as she navigates the trials of single motherhood, including addressing Luke's poignant questions about their family situation. In the midst of this upheaval, a shocking event occurs when Bif's date, Gerald, dies during an ill-fated striptease, forcing Sandra to reevaluate her circumstances.
As Sandra learns to cope, she finds solace through dance, slowly beginning to embrace the changes in her life, all while navigating feelings of reluctance when called to participate in a charity dance show. Meanwhile, Charlie's burdens come to light as he grapples with the reality of caring for his wife in a dementia care home.
With her marriage nearing its end, Sandra embarks on the difficult task of selling their beloved Tudor home, fueled by anger as she destroys Mike's tennis trophies with a wood chipper, with the help of Charlie and Ted, played by David Hayman. An unexpected encounter with Mike and Pamela at a pub serves as an empowering moment for Sandra, where she asserts her newfound autonomy.
As the charity performance approaches, Sandra joins Ted and Charlie in an unexpected celebration aboard their houseboats, which leads to Charlie revealing his audacious plan to sail across the Channel and explore the scenic canals of France. This spirit of adventure ignites something within Sandra, revitalizing her enthusiasm for life.
With holiday decorations and lights heralding the festive season, Bif's sudden absence adds a layer of mystery to the group's dynamics. In a turn of events, it is revealed that Bif is dealing with serious health issues, quietly undergoing medical testing for what later becomes a devastating lung cancer diagnosis, which she confides in Sandra and only Charlie.
As the group prepares for an Italian trip prompted by a performance invitation, the looming cloud of Bif’s illness hangs over their heads. During their time in Italy, they face the challenge of balancing joy with the pain of Bif's deteriorating health. The night before their departure, tragedy strikes as Bif passes away, leaving Sandra and Charlie shattered. In a heartfelt farewell, Sandra scatters Bif’s ashes in the tranquil Hampstead Heath Ponds, symbolizing their deep friendship and shared moments.
Amidst her grief, a letter from Charlie arrives, announcing the loss of his wife and his decision to sail to France, leaving Sandra at a critical juncture in her life. Faced with memories of her past dominated by Mike's disapproving attitude and Luke's innocent joy, she comes to the powerful realization that her previous life no longer defines her.
With the river beckoning, and Charlie already having departed, Sandra takes a daring leap of faith, choosing to leave behind the shores of her past for the uncertainty that lies ahead, finally embracing the future she once thought unimaginable.
