Passport to Treason (1956)

After being consulted by a friend concerning a murder case, a private eye learns the friend has become the next victim.
Passport to Treason was put together by Robert S. Baker and Monty Berman, the same team who’d later collaborate on the UK TV series The Saint. Rod Cameron stars as an American private eye, stationed in London. For the sake of a murdered friend, the detective takes over the dead man’s case, which turns out to have international ramifications. The villains are members of a phony pacifistic society, all of whom harbor plans for taking over the world.