Nigel Dobson (Hugh Grant) and his wife Fiona (Kristin Scott Thomas) are an impeccably respectable British couple who embody the essence of gentlemanly life. During their honeymoon cruise heading to India, they encounter a captivating young woman named Mimi (Emmanuelle Seigner), who is not only flamboyant but also exudes a Parisian flair. Through her, they are introduced to Oscar (Peter Coyote), an aspiring American author confined to a wheelchair. As he shares the tumultuous tale of his love life with Mimi, Fiona finds the story deeply unsettling and prefers to distance herself from its grim possibilities, while Nigel becomes increasingly entranced by the tumultuous love-hate relationship between the two.
Oscar seeks to dive into a world of intense sexual exploration with Mimi, a talented student dancer who eagerly indulges his every desire. Their relationship quickly spirals into a series of sadomasochistic encounters, revealing Oscar's darker side as he becomes increasingly cruel and dismissive towards her. When Mimi, wanting to leave this toxic situation, attempts to walk away, she finds herself drawn back into Oscar's orbit, forsaking her own happiness in an obsessive devotion to him.
Unfortunately, as their relationship descends into a nightmarish existence, Mimi loses her identity, surrendering her passions and everything that once defined her. She finds herself compelled to submit to Oscar's demands, knowing that if she does not, she risks being cast aside permanently. The situation worsens when she learns she is pregnant, holding onto the hope that this could lead to a conventional life together. Yet fate takes a cruel turn when Oscar, demonstrating his selfishness yet again, abandons her on their flight to Martinique under a flimsy pretext.
Mimi's life takes a devastating turn as she chooses to terminate the pregnancy, which results in a harrowing experience that leaves her physically and emotionally scarred, stripping her of her ability to conceive in the future. Meanwhile, Oscar resumes his care-free lifestyle, drowning in alcohol and fleeting romances, until a drunk-driving accident shatters his world, leaving him physically disabled. Yet, unbeknownst to him, Mimi, devastated but unable to move on, returns to Paris, fueled by a complex mix of love and resentment towards him.
Determined to impose her own brand of sadistic control, she becomes his caretaker in a twisted sense of revenge. In a series of psychologically torturous interactions, she seeks to manipulate him while simultaneously grappling with her deep, unresolved feelings. From trapping him in a cold bath to gifting him a gun with a single bullet, Mimi's grip on her volatile feelings and the remnants of their relationship clash dramatically.
As tension builds back on the cruise ship, Fiona's anxiety about Nigel's growing fascination with Mimi fuels her own desires for attention, leading her to flirt with others, including Dado (Luca Vellani). The shocking climax escalates when, in a moment of chaos and jealousy, Oscar shoots Mimi while Fiona and Nigel are left horrified, grappling with the violent end to a harrowing web of love, obsession, and psychological torment they have all become entangled in.
