Because boxing is a considered an illegal and disreputable enterprise in 1880's San Francisco, wealthy and influential members of the prestigious Olympic Club vow to make the sport a "gentlemanly" one. They sponsor a brash, extroverted young bank clerk named Jim Corbett, who quickly becomes an accomplished fighter under the new Marquis of Queensbury Rules. Despite his success, the young Irish-American's social pretensions and boastful manner soon estrange him from his benefactors, who plot to give their conceited former protege a well-deserved comeuppance. Despite this, his dazzlingly innovative footwork helps him to beat a succession of bigger and stronger men, and he finally finds himself fighting for the world's championship against his childhood idol, John L. Sullivan.

Mike Ribble was once a great trapeze artist - and the only to have completed a triple somersault - before his accident. Tino joins the circus, and manages to covince Mike to teach him the 'triple'. Meanwhile Lola, a tumbler, wants to get in on the act.

Bill's separated from his litter, making friends with the wild creatures until he's found and adopted by young Kathie. An accident separates him from her, and he's drafted into K-9 duty in the trenches until battle fatigue takes its toll and he turns vicious. And even though he finds his way back home, he may be condemned as a killer.

Tess and Sam work on the same newspaper and don't like each other very much. At least the first time, because they eventually fall in love and get married. But, Tess is a very active woman and one of the most famous feminists in the country; she is even elected as "the woman of the year". Being busy all the time, she forgets how to really be a woman and Sam begins to feel negleted.

Against all odds Father Flanagan starts "Boys' Town" after hearing a convict's story. Whitey Marsh comes there. He runs away but, hungry, returns. He runs away again but, when friend Pee Wee is hit by a car, returns. He runs away and joins his brother's gang. Flanagan and the boys capture the crooks and the reward saves the town.