In 1925, New York's governor Gov. Alfred E. 'Al' Smith [Walter Catlett] persuades state senator James J. 'Jimmy' Walker [Bob Hope] that the Democratic Party needs him to run for mayor of New York City. A concern on Jimmy's part is his estrangement from wife Allie [Alexis Smith], but he discovers that she is willing to go along with his political aims. The arrangement hinges on a blend of ambition, loyalty, and the uneasy feeling that personal life must sometimes be set aside for public duty.
Under the guidance of Chris Nolan [Paul Douglas], his political mentor, Jimmy wins the election in a landslide, capturing broad support and the hope of a transformed city. He later learns Allie has no intention of renewing their relationship; she is simply satisfied to be the great city's first lady, a role that carries ceremonial influence and social prestige but little personal closeness. This realization seeds a quiet strain in their marriage, even as Jimmy basks in electoral success and the adulation that follows a decisive victory.
A drunken Jimmy is found on a park bench by Betty Compton [Vera Miles], who takes him home, not knowing who he is. She scolds him for his behavior once she learns that the man she sheltered is the mayor, and a mutual attraction gradually takes hold. Jimmy leverages his political connections to help find her a job, beginning a cycle of favors and favors offered in the name of personal connection and political leverage. The relationship becomes a focal point as his administration faces scrutiny, and Betty finds herself drawn into a world where public image and private desire increasingly collide.
Such favors and graft become central to the 1929 reelection campaign, when opponent Fiorello LaGuardia mocks the mayor publicly and questions the current administration's integrity. Jimmy also confronts financial strain as the stock market crash bites, and Betty grows despondent over his inability—or unwillingness—to persuade Allie to consent to a divorce. The couple's private complications spill into the public arena, challenging Jimmy's popularity and testing the line between political charisma and ethical peril.
Still popular with the public, Jimmy is reelected, buoyed by a resilient image and a city hungry for progress. He tries to bring Betty to his victory party, but it is against his colleagues' wishes, a sign that the personal scandal is creeping closer to a breaking point. Tired of living in the shadows, Betty attempts suicide, an act that shocks the city and accelerates the unraveling of the mayor's carefully curated persona. She is hustled out of the country by Chris Nolan and impulsively marries a man who has been courting her, a move that propels the broader political drama toward an irreversible moment of truth.
The charges against Jimmy lead fellow Democrats to fear he could jeopardize Franklin D. Roosevelt's presidential prospects for 1932, casting a pall over his former support. Jimmy admits to having accepted bribes and favors, claiming that many successful politicians do so as part of the game, a defense that does little to restore faith in his leadership. His popularity erodes as critics and spectators alike question the ethics of his administration. Spectators at a Yankee Stadium game boo him for the first time, a stark public rebuke that underscores the shift in public sentiment. In a climactic voice from the field, Jimmy offers his resignation as mayor, signaling a turning point that forces him to confront the consequences of his choices. He decides to leave New York, and Betty—after a quick divorce—intends to join him, married or not, leaving a story that intertwines ambition, love, and the costs of power.
