The Wagons Roll at Night: An escaped circus lion provides the impetus for the meeting of carnival owner Nick Coster and Matt Varney, a small-town man who suddenly becomes a lion tamer when he manages to subdue the big cat. While acclimating to carnival life, Matt begins a romance with Nick's sister, Mary, causing tension between Matt and Nick. The latter must also juggle his stormy relationship with glamorous circus star Flo Lorraine.