As Peggy Sue Bodell (/actor/peg-sue) steps into the nostalgic setting of her 25-year high school reunion in 1985, she arrives with her daughter Beth. The atmosphere is a mix of warmth and awkwardness, amplified by the absence of her estranged husband Charlie (/actor/nicolas-cage), a painful reminder of their recent separation due to his infidelity.
While Peggy Sue reconnects with former classmates Maddy and Carol, she deliberately avoids Charlie, choosing instead to rekindle friendships that were once the cornerstone of her high school life. The night takes a surprising turn when the emcee announces the reunion's "king and queen": Richard Norvik, a once-misunderstood class geek turned billionaire inventor, and Peggy Sue herself. Overwhelmed by the unexpected honor, she faints on stage as she's crowned.
Upon regaining consciousness, Peggy Sue finds herself inexplicably transported back to 1960, in her senior year of high school. Disoriented and struggling to comprehend her new reality, she decides to return to her parents' home to blend into her former life. Desperate for clarity, Peggy Sue reaches out to Richard (/actor/kathleen-turner), hoping his perspective might help unravel her tangled situation.
As Peggy Sue navigates this familiar yet alien landscape, she begins forming an unlikely connection with Richard. Initially, he is skeptical of her strange claims, but as she reveals certain details about events yet to transpire, he becomes convinced of her sincerity. This newfound understanding prompts Peggy Sue to reassess her relationship with Charlie and to consider making a definitive break.
However, before ending things fully, she allows herself one more night of intimacy with Charlie after a party, only for him to panic and remind her of their recent split. Rather than retreating home, she finds distraction in an all-night café, where she meets Michael Fitzsimmons, a free-spirited loner who has always intrigued her.
Their conversation flows easily, marked by laughter and relatable stories, revealing a deeper connection beneath their quirky facades. The two share a ride on Michael's motorcycle, leading to a starlit reunion that awakens feelings Peggy Sue thought she had buried.
The next night, Peggy Sue finds herself at a local music bar, where Michael expresses his desire for a polyamorous relationship involving her and another woman. Politely declining, she encourages him to seek inspiration from their shared connection instead. Circumstances change when Charlie takes the stage, and Peggy Sue gains a new perspective on her former lover as she watches him perform.
Meanwhile, Charlie's music career faces disappointment when a talent scout fails to see his potential. As the night drags on, Peggy Sue confronts a pivotal choice regarding her relationships and future.
The following day, she tries to discuss her feelings with Charlie, but his frustration over his music career bubbles over, leaving her feeling disheartened. Seeking comfort, she finds refuge with Richard, voicing her hope to escape their toxic cycle—especially for Charlie, whose dreams were overshadowed by her unplanned pregnancy. Richard offers a proposal, but Peggy Sue declines, realizing they are both too young for such a serious commitment, especially considering his future aspirations.
As Peggy Sue’s 18th birthday approaches, she visits her grandparents and shares her extraordinary experiences. Her grandmother’s confession of psychic abilities piques Peggy Sue’s curiosity, prompting her to confide in her grandfather. He then introduces her to a Masonic lodge where members perform an ancient ritual meant to send her back to 1985. Just as the lights dim, Charlie bursts in, taking Peggy Sue away, leaving the lodge members convinced the ritual worked.
In the present, Charlie reveals he plans to abandon his musical dreams for the family business, offering Peggy Sue the locket she had from the film's start, along with a heartfelt proposal. Gazing at the childhood pictures inside the locket, Peggy Sue experiences a moment of clarity—realizing that they are destined to be together. Their passion reignited, they come together, succumbing to their desire.
Peggy Sue awakens in a hospital bed in 1985, with Charlie by her side. As she recuperates from her ordeal, he presents her with Michael's written tribute, dedicated "To Peggy Sue and a Starry Night"—hinting at the legitimacy of her time-travel. Regretting his past mistakes, Charlie begs for forgiveness and a second chance. Reflecting on her grandfather's remarks about her grandmother's strudel being the glue of their family, Peggy Sue invites Charlie to dinner with a gentle smile, saying, "I'll bake a strudel."
