Road to Rio

Scat Sweeney and Hot Lips Barton team up with Lucia, a glamorous nightclub singer, and join her on clarinet and trumpet as back‑up musicians. They are refugees from a disbanded swing quintet and hope to find steady work while avoiding entanglements with girls. The trio sets out to make a living by performing across the United States.

The pair travels the country in search of work, repeatedly scattering from one town to another whenever a girl catches their eye. When gigs dry up, they decide to stow away on a ship bound for Rio. The voyage marks a turning point as their paths intersect with Lucia again.

With the search for work stalling, Scat and Hot Lips sneak aboard a ship headed to Rio and hope to stay out of trouble. They encounter Lucia, who initially thanks them for their help but then hands them over to the captain. Unknown to them, Lucia is under hypnosis by Catherine Vail.

Lucia's gratitude turns to involvement with Vail's schemes as she is manipulated and handed over to the ship's captain. Catherine Vail uses hypnosis to control Lucia and plots to marry her to her brother in order to seize control of important papers. The ship becomes a stage for hidden treachery.

Back in the United States, a nightclub owner hires Scat and Hot Lips but expects the full swing quintet. To fill the gap, they recruit three local musicians, the Wiere Brothers, who cannot speak English, and coach them with a few phrases in jive talk. The plan is to fool the owner into believing they have the complete band.

Scat and Hot Lips train the Wiere Brothers, teaching them a handful of jive phrases to simulate a real brass‑dominated swing quintet. The Brothers' earnest attempts and language barrier create comic moments as they rehearse for the gig. The act gradually comes together for the nightclub performance.

Catherine Vail intensifies her scheme to rid herself of the musicians and secure Lucia's papers. She hypnotizes Scat and Hot Lips and pushes them toward a deadly duel in an attempt to eliminate their interference. The danger heightens as the guardian tightens her grip on Lucia.

Realizing something is wrong, the duo deduces that Vail's plan is to eliminate them and derail the wedding. They rush to thwart the marriage and catch the criminals, seizing the papers to prevent manipulation. The tension escalates as they move to disrupt the conspirators' plans.

During the confrontation, Scat seizes the mysterious papers and reads their contents before tearing them up. He cryptically tells the audience that 'the world must never know,' signaling that the information must be kept secret to protect Lucia and the schemes.

After the upheaval, Scat discovers that Lucia loves Hot Lips, not him. A keyhole glimpse reveals Hot Lips hypnotizing Lucia, exposing the control behind her romantic entanglements. The revelation shifts the emotional stakes for everyone involved.

With the manipulation exposed, Scat and Hot Lips rush to stop the wedding and confront Catherine Vail and her conspirators. They pursue the crooks and prevent the ceremony from proceeding, steering the story toward a lighter resolution.

Jerry Colonna appears in a cameo leading a cavalry charge to rescue Bing and Bob, as the film cuts away to galloping horses. The sequence is used for comedic effect, and Colonna quips that they never quite made it, adding a playful note to the action.

The plot resolves before Colonna can arrive, with the crooks thwarted and Lucia's fate clarified, leaving the performers to conclude on a bright, musical note. The ending emphasizes camaraderie and the film’s lighthearted tone.