I have seen this movie a few times over the years. All the actors who appeared in this movie were household names at the time, many of them went onto bigger things such as Sean Connery, Patrick McGoohan, Herbert Lom, Peggy Cummins, and of course Stanley Baker.
I cannot imagine a movie being made today with so many household names appearing in a single movie.
The lovely Peggy Cummins is still alive today, although many of the original cast are now long gone. Everbody who loves good old British movies should have a copy of this.