In 1968, during filming of the war movie "The Bridge at Remagen", co-starring Gazzara and friend Robert Vaughn, the Soviet Union and its allies invaded Czechoslovakia. The cast and crew were detained for a time; filming was later completed in West Germany. During their departure from Czechoslovakia, Gazzara and Vaughn assisted with the escape of a Czech waitress whom they had befriended. They smuggled her to Austria in a car waved through a border crossing that had not yet been taken over by the Soviet army in its crackdown on the Prague Spring.