As was his custom, producer/director Stanley Kramer made some iconoclastic casting decisions when mounting his $5 million production The Pride and the Passion. Adapted from The Gun, a novel by C. S. Forester, the film is set in Spain during the Napoleonic wars. Captain Anthony Trumbull (Cary Grant), a British military officer, is ordered to retrieve a large and unwieldly abandoned cannon, then transport the weapon to the British lines, where it will be used to attack the French garrison at Avila. Hotheaded guerilla leader Miguel (Frank Sinatra) agrees to help Trumball move the cannon over hill and dale, even though he hates the Englishman's guts. Tagging along on the arduous odysseys is Miguel's fiery mistress Juana (Sophia Loren), who develops a yearning for the stolid Trundall (then-lovers Loren and Grant would later be teamed in Houseboat). Pride and the Passion made a mint at the box-office for both Kramer and United Artists.
by Hal Erickson synopsis