The Big Circus

The Big Circus is a 1959 film starring Victor Mature as a circus owner struggling with financial trouble and a murderous unknown saboteur. It was produced and cowritten by Irwin Allen, later known for a series of bigbudget disaster films.

Hanks top act is the Colino trapeze troupe, featuring family patriarch Zach Colino Gilbert Roland and newcomer Tommy Gordon David Nelson, as well as ringmaster Hans Vincent Price and clown Skeeter Peter Lorre. Unknown to Hank, his little sister Jeannie Kathryn Grant has held a lifelong ambition to fly on the trapeze and has been secretly training with the Colino act for the past year.An unknown saboteur sets a lion loose at a party thrown to celebrate the start of the circus season, terrifying the VIPs in attendance until Hank manages to capture it with the help of Colino. Helen accuses him of staging the incident for publicity. Subsequently, they discover the lions cage had been deliberately opened. ........

Source: Wikipedia