Sheppard, Gage and another man are captured by Nazis. Sheppard is given a water torture and beaten, while the others are hung from hooks. Eventually, they realize they can escape by unscrewing the hooks.
If the visual style looks familiar, it's because this was produced by the people responsible for The Man from U.N.C.L.E.   This 1966 series took the spy derring-do from UNCLE and placed it against the very serious backdrop of World War II. It lasted less than a season on CBS.