The Naked Runner (1967)

Sam Laker is an American industrialist working in Britain who has just been awarded an international award for industrial design He is planning to travel to East Germany to attend a trade show and show off his invention taking his 10 year old son with him for a holiday Meanwhile a British Intelligence officer who served with Laker in the Second World War decides to use the opportunity of Lakers trip and his lack of an intelligence profile to coerce him into carrying out an assassination