Based on elements within Edgar Rice Burroughs's 1912 novel, "Tarzan of the Apes," Greystoke begins in the late 19th century, where a young couple born into Scottish nobility, Jack Clayton and his pregnant wife Alice, find themselves shipwrecked off the coast of Western Africa. Months later, they give birth to a boy who quickly becomes an orphan when his mother dies of malaria, and his father is killed in an altercation with nearby apes. One of the apes adopts the human baby as her own. When the boy grows into a man, he takes on the alpha male to become the leader of the tribe.

Meanwhile, an expedition arrives nearby for specimens for the British Musem. The expedition gets viciously attacked by a native village. Surviving the slaughter is a Belgian named Phillippe d'Arnot, whose life is saved and wounds tended by the mysterious ape-man. Phillippe realizes his savior is the son of the married couple, the Claytons, who built the abandoned cabin in the vicinity. Dubbing the jungle man "John Clayton', d'Arnot teaches him to speak, move, and behave like an aristocrat from civilized society before taking him to his ancestral estate in Scotland to reunite with his grandfather, the Earl of Greystoke. There, John develops feelings for grandfather's ward, an American-raised woman named Jane Parker.

Christopher Lambert, Ralph Richardson, Ian Holm, Andie MacDowell, James Fox star. Hugh Hudson directs.