What’s Up, Doc?

Dr. Howard Bannister travels from Ames, Iowa to San Francisco to compete for the grant. He checks into the Hotel Bristol with his tightly wound fiancée Eunice Burns, and soon he meets Judy Maxwell in the hotel's drugstore. This initial encounter sets the tone for the forthcoming comic chaos as different agendas collide.

On the same floor, the bags are mixed up as four parties unknowingly take one another's cases. Howard discovers his plaid overnight bag holds igneous rocks with musical properties, while others carry top-secret papers, jewels, or Judy's clothes and dictionary. The mistaken exchange seeds the pursuit of prized items throughout the night.

Judy disguises herself as Eunice to attend the musicologists' banquet and try to win the grant through charm and wit. Howard publicly denies knowing the real Eunice when she makes her entrance, sabotaging her plans. The deception heightens the competition and deepens the growing tension between Howard and Judy.

Judy slips into Howard's hotel room, attempting to hide from Eunice, but their encounter triggers the thieves' ongoing attempt to recover their items. A fire erupts during the struggle, destroying the space and accelerating the night's chaos. The escape and misdirection continue to braid the lives of all four bag-owners.

By the next morning, the bags have effectively swapped contents: Howard ends up with the jewels, Judy with the government papers, Mr. Smith with Judy's clothes, and the thieves with the igneous rocks. The muddled ownership fuels new deceptions and shifts in pursuit. The stage is set for further chaos as the group heads toward the reception.

At Frederick Larrabee's upscale Victorian home, a formal reception erupts into a chaotic melee as rival sides battle over the bags and secrets. Guns, furnishings, and pies fly as the confrontation escalates. The scene cements the fallibility of all the adults and underscores the ridiculousness of the pursuit.

Howard and Judy seize all four bags and flee the scene on a delivery bicycle. They weave through crowded streets while the pursuers close in, testing their improvisational teamwork. The chase also deepens the romantic tension between them.

They hijack a decorated Volkswagen Beetle from a wedding party to continue the getaway, increasing the odds against them. Mr. Smith, Mr. Jones, and the jewel thieves pursue relentlessly, adding danger to the already chaotic escape. The chase pushes them across neighborhoods and into new dangers.

Chinatown becomes the arena for the escalating chase as they disrupt a parade and race down Lombard Street. They crash through a glass panel and plow through wet cement, ending up near the ferry landing on the San Francisco Bay. The sequence blends slapstick pursuit with cityscape obstacles.

All parties converge in a courtroom where Judge Maxwell attempts to untangle the mess. He is overwhelmed by the chaos and ends up uncovering Judy's role in much of the trouble. The judge orders that the bags be sorted and the owners restored.

Mrs. Van Hoskins pays for the considerable damage and divides the remaining $50 reward among those who helped retrieve her jewels. The trial and revelations settle some financials, while the grant's fate remains tied to the plagiarist disclosure. Eunice's future is hinted at as she drifts away from Howard.

Simon is revealed as a plagiarist, which clears Howard for the grant. Eunice reveals her affection for Larrabee and leaves Howard for him, ending their engagement. The main romance shifts to Howard and Judy as the true pair.

Howard boards a plane back to Iowa, only to discover Judy in the seat behind him. He proclaims his love and apologizes for his earlier words, and Judy replies with the famous line 'Love means never having to say you're sorry' as they kiss. The scene closes with a Looney Tunes cartoon What's Up, Doc? playing on the plane.