Powell and Pressburger together gave us a string of classics of 1940's British Cinema, pictures that were original, daring, and visually stunning. Other than perhaps Hitchcock, I would consider them the first "auteurs" of the cinema.
They also introduced US audiences to some of the greats of British film - among them Deborah Kerr, Wendy Hiller, Roger Livesey, and Sabu. In addition, they, along with their regular cinematographer Jack Cardiff, explored the use of color and lighting, so that you recognize one of their pictures the moment you come into it. And the really cool thing is that they did it together.
The Life and Death of Colonel Blimp - The life of a young British Army officer, from the Boer War up to World War II, the regrets and sacrifices, and the effort to remain relevant in a fast-changing empire. Notable for Roger Livesey's starring role, and for Deborah Kerr playing three different women important to him at various stages.
I know Where I'm Going - Wendy Hiller, on her way to a Scottish Isle to join her much-older fiance, runs into foul weather and is forced to remain in the village of Mull, where she meets the young Laird, Roger Livesey. Will she choose a life of wealth and convenience, or a life of love?
Stairway to Heaven (a.k.a. A Matter of Life and Death) - David Niven is an RAF pilot who's about to crash, who connects over his radio with operator Kim Hunter, and falls immediately in love. Complications ensue because he was supposed to be taken to Heaven, but his angelic escort missed him. Now, he needs to fight for his right to remain on earth and be with the woman he loves. Notable for it's use of color, as well as black and white, and for his argument before a historical and heavenly jury.
Black Narcissus - Deborah Kerr is leader of a group of Nuns, who take over an old abbey high in the Himalayan mountains. The exotic culture and mysterious atmosphere begin to have a damaging effect on the sisters and their psyches. Notable for it's use of color and for the claustrophobic atmosphere it creates. Watch for a very young Jean Simmons as Kanchi, a Himalayan dancing girl.
The Red Shoes - The story of a young ballet dancer, torn between her desires to become a prima ballerina under the guidance of an obsessive dance master, and her love for a young composer. Notable for not just it's brilliant color, but it's casting of actual dancer Moira Shearer in the lead, and for it's use of ballet to tell much of the story.