Ulysse Mérou was the main protagonist of the French novel La Planète des singes. He was a journalist and a friend of Professor Antelle. He accompanied Antelle and his colleague Arthur Levain on a mission to the giant red sun Betelgeuse. On the nearby planet of Soror, they encountered a tribe of primitive humans, and Ulysse met the female, Nova.
After Ulysse was captured by the intelligent apes that dominated the planet, he befriended two chimpanzees, Zira and her fiancé Cornélius. He fell in love with Nova and impregnated her, ultimately escaping back to Earth along with Nova and their newborn son Sirius from the alien ape planet. He discovered that Earth had meantime been taken over by apes too. His first-person journal (which formed the narrative of the book) was left floating idly through interstellar space in a cheap glass bottle, to be found by space-travellers Jinn and Phyllis.
- The character of Ulysse Mérou inspired 'George Taylor' (originally 'John Thomas'), the protagonist of the movie adaptation, Planet of the Apes. Taylor's fate remained largely unchanged, except that in the original book he was a journalist accompanying the mission, rather than its leader; and he ultimately escaped back to Earth from an alien ape planet and discovered that Earth had meantime been taken over by apes too, rather than discovering the alien planet was actually Earth.