This is a great B&W film, highly recommended and with what must be "probably the best ending in the world ever"

I judge a good film by the number of times I want to and, do watch it. This one gets an airing at least once a year.

John Mills leads a brilliant cast who are brought together in a military ambulance as they try to escape Rommel's advance on Tobruk.
They have to drive across the desert to Alexandria meeting German patrols, experiencing vehicle problems and fighting natures elements of danger.

Mills plays a tired army captain whose nerves are shattered by the war and has turned to drink.
Harry Andrews is the mechanic and displays enormous calmness as he nurses a failing vehicle in the middle of the desert.
Quayle appears as a mysterious South African who gets picked up along the way.
Sylvia Sims flashes her eyes at Mills like Princess Diana.

Has one of the classic endings to any film.

There are no special effects; it's in black & white; it relies on good acting. Watch it.