Mission: Impossible (1966)

Season 7: Episode 11

Crime boss Metzger determines that the IMF was responsible for the heist at the Aquarius Casino (from last season's episode ""Casino"") and kidnaps Jim when he and Barney are on vacation, forcing the IMF to work for him to recover evidence against him from a safe deposit box. The evidence, a letter, is being used as a bargaining chip by Metzger's former crony, Connally, to get Federal immunity for his testimony. Casey and Willy manage to steal both keys to the box and get the letter, except Metzger's subordinate Hawks steals the letter to blackmail his boss. Barney comes up with a fake letter and use it to get to Jim where the IMF takes everyone into custody.