In this delightful story about love's unexpected chemistry, Corie (Jane Fonda), a vivacious and spirited woman brimming with enthusiasm for life, finds herself married to Paul Bratter (Robert Redford), a meticulous man who thrives on order and stability. The couple embarks on their journey as newlyweds in a snug fifth-floor apartment in Greenwich Village, where each step to their home literally counts, as they transport themselves up five flights of stairs. Eager to convert their humble living space into a cozy sanctuary, Corie is met with resistance from Paul, whose nature is far more reserved.
The colorful tapestry of their neighborhood introduces them to an array of lively characters, including the quirky Victor Velasco (Charles Boyer), who resides in the attic of their building. His eccentric lifestyle becomes an invigorating influence on Corie, as they join forces to address the apartment's various oddities, dealing with everything from fickle heating systems to troublesome leaks. As their friendship deepens, tensions rise as Victor flirts with Corie, creating an unease for Paul.
To bring some excitement into her mother Ethel Banks' (Mildred Natwick) life, Corie decides to organize a dinner outing with Victor. They all venture to a charming Albanian restaurant on Staten Island, indulging in sumptuous cuisine, vibrant music, and even a spirited dance with a belly dancer. The playful interactions between Corie and Victor leave both Paul and Ethel bemused, caught in a mix of laughter and confusion.
As the night winds down, Victor escorts Ethel home, while Corie and Paul return to their apartment. Their contrasting personalities create an increasingly evident rift; Corie yearns for spontaneity and thrill, while Paul seeks the comfort of predictability. As delicate snowflakes blanket the ground outside on that cold February night, they retreat to their respective corners—the cozy bedroom for Corie and the couch for Paul, which occupies a space under a leaking skylight.
With time, Paul's health takes a downturn, and despite his feverish state, Corie is adamant about ending their marriage, declaring her wish for a divorce. The atmosphere in the apartment thickens with unspoken words as they navigate their estrangement. Eventually, Corie's boiling frustration leads her to demand Paul leave, sending him away into the night.
A wave of concern washes over Corie when she learns from her aunt that Ethel never returned home. Panic sets in as the reality hits that Ethel had spent the night at Victor's apartment after a fall on slick stairs, causing her to appear in only her undergarments and Victor's Japanese kimono—an unexpected turn of events.
While Paul struggles with the collapse of his marriage, he seeks solace in a drink, abandoning his responsibilities to find refuge in Washington Square Park. Determined to reconnect with Paul, Corie ventures out to locate him and eventually discovers him in a state of drunken abandon at the park.
With her mother's advice echoing in her mind, Corie takes it upon herself to bring Paul back to his senses, chasing him as he careens unpredictably through the park. The formerly cautious Paul embraces a fresh wave of carefree abandon, albeit to Corie's growing concern. He soon declares that he has taken ownership of this newfound territory and leads them back to their apartment.
Upon their return, Paul's drunkenness escalates, leading him to ascend to the rooftop in an apparent quest to escape the turmoil below. Corie, frightened for his safety, pleads with him to come down—her desperate cries reverberating through the skylight as he teeters on the edge.
In a tug of words, Paul demands that Corie acknowledge his inebriation, while she resists, recalling her previous admonitions about his overly cautious demeanor. As tension mounts, Paul grows increasingly restless, fear gripping him as he seeks a way back down.
In an effort to soothe her husband, Corie urges him to sing an Albanian folk song they had delighted in at Victor's restaurant, hoping to calm his frayed nerves. As Paul's voice echoes through the night, Corie takes a brave leap to climb up to the rooftop, intent on reuniting with him.
As she reaches for Paul, a crowd gathers below, drawn in by the unfolding spectacle, while Ethel and Victor, blissfully unaware of the dramatic events above, arrive to contribute to the surreal scene.
Ultimately, Corie's unwavering determination meets Paul's desperation as they share a heartfelt kiss, leading them back down to the solid ground, where grateful onlookers cheer for their reunion and the beginnings of their new chapter.
