Someone wanting to get better acquainted with decent old films could do an awful lot worse than work through the list of films on IMBD to which Eric Ambler contributed in some way.
Journey into Fear, 1943 - a curiosity, adapted by Joseph Cotten and Orson Welles from a novel by Ambler, with Welles and Cotten in the leading roles and various actors who often worked with them also in the cast.
The Way Ahead, 1944, directed by Carol Reed, adapted from Ambler's novel by Peter Ustinov. I'm a sucker for British WW2 films and this is a pretty good one. David Niven, Stanley Holloway and James Donald. Follows a group of raw recruits to the army to their deployment in North Africa. (See also Millions Like Us.)
The October Man, 1947. Stars the wonderful John Mills and Joan Greenwood. Directed by Roy Ward Baker ...
Who went on to direct A Night to Remember (1958), which stars Kenneth More and knocks Titanic into a cocked hat.
Screenplay for The Cruel Sea (1953), the ultimate WW2 navy and duffel coats film. Stars Jack Hawkins, Donald Sinden, Denholm Elliott and Stanley Baker.
Apparently EA contributed to the script of David Lean's Oliver Twist in 1948 too.
I haven't seen The Magic Box from 1951, but as it stars the glorious Robert Donat I really should seek it out.