Mogambo (1953)

Victor Marswell runs a big game trapping company in Kenya. Eloise Kelly is ditched there, and an immediate attraction happens between them. Then Mr. and Mrs. Nordley show up for their gorilla documenting safari. Mrs. Nordley is not infatuated with her husband any more, and takes a liking to Marswell. The two men and two women have some difficulty arranging these emotions to their mutual satisfaction, but eventually succeed.