1970's Drama / spies/ Detective style Movie

I watched a movie when I was young, and even though I can't remember its title, I recall the plot. The film was about dramatic espionage and the pursuit of a spy. I remember a scene involving a struggle, where a man strangled a blonde woman and killed her with an airplane wing pin. It was a dramatic and intense moment on screen. The film was set in America and it featured many actors and actresses who would go on to become big names in the future.