Shake Hands With the Devil (1959)

In 1921, Kerry O'Shea (Don Murray), an American medical student living in Ireland, learns that his esteemed professor, Sean Lenihan (James Cagney), is also a leader in Ireland's rebel army. Even though Kerry's father and roommate have both been killed by British troops, he refuses to join the Irish rebellion. However, after Kerry is unjustly imprisoned and tortured by the British "Black and Tans" special forces, he fully commits himself to the cause of Irish freedom.