Colonel Helmut Kellerman is the main antagonist in an episode of 1966 series of Mission: Impossible. He is played by Anthony Zerbe.
Colonel Helmut Kellerman began suspecting something about Orin Selby, who became a high ranking member of the enemy's intelligence service. Kellerman recently captured a courier, code-named Marceau, who knows that Selby is an American agent (since Marceau was the American agent who arranged for Selby's "escape" from America, although they were using code-names and if Kellerman can get Marceau to talk he could put it all together).
Jim Phelps and the IMF team come into get Marceau out, to prevent Selby's cover from getting exposed and put an end to Kellerman's threat, they have to convince Lt. Albert Brocke, a young military aide, that Kellerman is a traitor.
Kellerman has Marceau strapped upside down and attached with a detonator, if someone tries to save him.
Rollin Hand, an IMF team member, uses a special lighter, which sprays knockout gas, only him and Jim aren't infected (due to taking pills to become uninfected).
Barney Collier, an IMF team member, puts liquid nitrogen to freeze the bomb, after successfully freezing the bomb and the team unstrapped Marceau and escaped. Rollin gave Brocke an injection of the antidote, to revive him. Kellerman came too and discovered Marceau was gone, Brocke pointed a gun and killed him.