Wimpy sailor boy Billy Epsom has just arrived from New Guinea with a guinea pig in a box for his sweetheart. But today’s newspaper headline reads, “Guinea Pig With Deadly Germs Roaming Our Streets”. Billy causes havoc at the Yellow Cab stand when a cabbie catches sight of his cute little “piggy”. Billy sets out to see his girl at her father’s mansion. On the streetcar, he takes the guinea pig out of its box. Soon passengers and driver are diving off, and the runaway car is gaining on a dynamite truck! Billy reaches the Von Ratseller mansion where a tough army sergeant is his rival. Army sergeants are terrified of navy guinea pigs, at least until they learn that the disease-ridden rodent never actually escaped from the zoo. Fortunately for Billy, a public health assault squad armed with gas masks and disinfectant sprayers shows up and starts spritzing. Everyone gets giddy and collapses. The addled Billy takes the opportunity for a smooch with his girl. And when they start to lose their nerve, there’s always another giddy spritz from that spraygun.