After marrying Baronet Clifford Chatterley (Matthew Duckett), Constance "Connie" Reid (Emma Corrin) relocates from bustling London to the grand Chatterley estate in Wragby. Their marriage is consummated, yet immediately after, Clifford heads off to World War I. When he returns weeks later, he is paralyzed from the waist down, requiring full-time care. The couple’s caretakers, Mr. and Mrs. Warren, try their best to help, but as time passes, Connie finds herself increasingly burdened by Clifford's handicap and his emotional detachment.
Despite employing various staff to assist around the estate, Clifford insists that Connie remains by his side to take care of him personally. While Clifford delves into writing a novel and hosting literary gatherings, Connie grows restless and is denied a visit to her sister Hilda (Faye Marsay) in London, as Clifford needs her around. To escape her mounting suffocation, Connie begins to take long strolls across the estate and soon discovers the miners in their village protesting against harsh working conditions.
Amidst their complex situation, Clifford, longing for an heir, suggests that Connie have an affair solely for conception. However, his novel receives a scathing review, critiqued as old-fashioned and self-absorbed, further straining their relationship. During Hilda's visit, she notices Connie's deep fatigue and hires Mrs. Bolton (Joely Richardson), a former caretaker from Clifford's youth, to assist him—much to Clifford's disapproval. Hilda also insists Connie see a doctor for her well-being.
It is during an afternoon errand involving pheasant chicks at a nearby cottage that Connie encounters Oliver Mellors (Jack O'Connell), the reserved gamekeeper who, like her, has returned from war only to find heartache—his wife, Bertha, having left him for another man while they remain un-divorced. Seeking solace, Connie continues to visit Oliver's cottage, relishing in the quiet moments where she can read undisturbed. Meanwhile, while Clifford remains focused on maintaining the mines, Connie wishes to aid the miners in seeking a brighter future.
As her interactions with Oliver deepen, a palpable and passionate connection ignites between them, flourishing into a fervent sexual relationship. Under the guise of tending to the chicks and prolonged walks, Connie visits Oliver frequently, and their intimate adventures unfold amidst the woodland surrounding the estate.
However, Mrs. Bolton becomes suspicious upon spotting Oliver on the estate grounds during one of Connie's outings. The miners' plight worsens under Clifford's tenure, and Connie, feeling hopeful, informs Mrs. Bolton that Clifford's recovery is progressing, and an heir may still be possible—a rumor that Mrs. Bolton spreads throughout the villages.
Connie, realizing her early signs of pregnancy, suggests to Clifford a trip to Venice with Hilda, as a pretext for her affair, simulating an effort to conceive. Oliver, heartbroken and feeling used, confronts Connie, insisting she truly loves him. Connie, disillusioned with Clifford's aristocratic view of superiority over the working class, runs to Oliver during a storm. Tragically, Mrs. Bolton finds them engaged in an intimate moment hidden in the woods shortly after.
When Hilda learns about Connie's romance with Oliver, disappointment washes over her, but she ultimately leaves Connie to enjoy their last night together. Complicating matters further, Ned, Bertha's new partner, shows up at the cottage seeking his share of the war pension and uncovers evidence of Connie's presence, prompting him to spread slanderous rumors about both Oliver and Connie.
Upon hearing the gossip, a furious Clifford dismisses Oliver from his position just as Connie returns from Venice. In a bold confrontation, Connie declares her love for Oliver and reveals her pregnancy, while Clifford obstinately refuses to grant her a divorce.
As Connie embarks on her journey back to Venice, Mrs. Bolton promises to spread the word about her search for Oliver. This tale of love and sacrifice reveals the heartfelt truth: a Lady abandoned her title and riches for the simple yet profound love of a gamekeeper.
Months later, disenchanted with life’s constraints, Connie returns to England, only to learn that her story has resonated throughout the community: a noble woman left everything for love. Eventually, a letter from Oliver finds its way to Connie, inviting her to join him in Scotland. She drives nearly 800 kilometers, yearning to share a humble life in the serene countryside with the man she loves.
