Over the past week, I watched the first three original Planet of the Apes movies. I didn’t know the stories. I knew only what anyone familiar with sci-fi over the years would know, a plot point even the sequel spoils in its own trailer. But the whole movie doesn’t turn on that revelation. It was just an interesting surprise to 1968 moviegoers–no doubt part of what made it a successful movie.

You’ve heard that the original Star Wars and Jaws movies were blockbusters that changed moviemaking ever since. You probably know parts of the score from those movies. They have a tone of adventure that feels like a movie. Planet of the Apes leans into the strange and alien. This trailer captures that tone with minimal spoilers. The score invokes the wild unknown of 1960s sci-fi. It isn’t the music of adventure but of survival.

The director, Franklin J. Schaffner, wants us to experience the space crew’s voyage and their crash landing in a sea. We see water breaking through ship’s seems as if in the crew cabin ourselves. The three-man crew drag themselves to shore, and the first real cynicism comes for Taylor (Charlton Heston) laughing loudly at his earnest crewmate planting a pocket-sized US flag next to the water. The crew treks through a canyon wilderness, afraid that, though the air is fine, there may be no drinkable water or living plant life.

The first 30 minutes follows this track. Will they survive or won’t they? This kind of story tension gets me scratching my head, because if you tell viewers upfront the apes rule the planet, how long will they tolerate the main characters scrambling along on their own? Maybe if we were learning about the crew as well-rounded men, it would be more interesting. But we only get the wilderness and three men looking for water.

On the other hand, Richard Schickel wrote in Life Magazine, May 10, 1968, it was the best American movie he’d seen that year–“faint praise,” he says, “considering the competition,” but still he and his four-year-old daughter loved it.

I had thought the first film was going to focus on racial tolerance or bigotry, but it’s really an anti-war movie. The ape society is governed by religious zealots who won’t tolerate evolutionary theories and stamp out any hints of civilization beyond their own. God made apes in his own image, they say. Humans are just mute wildlife. Most of the hostility is in apes treating humans as non-sentient animals, and the story is driven by the threat Taylor poses to their carefully managed social order. The overarching theme, which starts with questions from the crew after they abandon ship and resumes with chimpanzee Cornelius revealing his exploration of ancient human ruins, is the question of what happened to humanity. The authorities won’t tolerate open discussion of humans once having civilization or being anything more than they are today. For viewers, though, if humans were more on this planet, what happened to them?

That’s what the famous scene at the movie’s end hammers home. Taylor realizes he didn’t crash on another planet. He returned to Earth 2000 years later, long after mankind had destroyed civilization through endless warmongering and the A-bomb.

Planet of the Apes (1968) is good period sci-fi. There are things to complain about (like the fact the humans are described as being unable to speak but in fact they are completely mute —they never make a sound), but it’s a good story. I laughed at the scene of government leaders being confronted with facts and ideas they rejected.