The future distant future of Planet of the Apes is hazy. In the first two classic films, Taylor and Brent travel from the relative present of the 1970s to a period in the future — 3978 or 3955, depending on whether you’re watching the first film or the sequel Beneath the Planet of the Apes. The subsequent sequels — Escape from, Conquest of, and Battle for — the Planet of the Apes, revealed a timey wimey paradox at the center of the Apes mythos. In the original films, the future world of the first two films actually bootstrapped the past thanks to Caesar (Roddy McDowall) actually having parents from the 3900s.
