Circus tells the story of an American named Marion who is banished from the US because a black man impregnates her. Marion escapes to Russia to start a new life in the circus and joins up with lustful, anti-Russian ringmaster who happens to be in love with her. The ringmaster knows her secret about the black baby and threatens to reveal it unless she marries him. The problem is that Marion has fallen in love with a Russian acrobat and later out of sheer jealousy, the ringmaster reveals the identity of the woman's child in front of the circus audience.