The Wonder Circus comes to a town in the Midwest with its featured attraction, Jumbo the elephant. Pop Wonder owns the circus, but his continued gambling losses in crap games leaves him (and the circus) with an ever-growing number of IOUs.
His daughter, Kitty Wonder, hires a newcomer, Sam Rawlins, as both a performer and tent hand. She is unaware that Sam is the son of circus mogul John Noble, whose ambition is to buy the Wonder Circus for himself. Noble has been quietly buying up the IOUs with Sam's help and abruptly takes control of the family's business, leaving the Wonders without a show.
Kitty, Pop and his longtime fiancee Lulu go off on their own, forming a traveling carnival, but it isn't quite the same. Sam, however, has fallen in love with Kitty and has a guilty conscience about what he has done. Sam splits from his father and rejoins the Wonders, bringing with him an old friend of theirs, Jumbo.