So, the movie already starts on weak footing. It tries to continue a story that, in my view, was closed and finished and needed nothing else. And it does a very weak job in trying to achieve it anyway.


[spoiler] You have to be very lenient from the beginning. The explanation how the second ship got there is already soft and by shear coincidence Brent meets Nova right then and there. The story then just wafts along and you see the budget cut's at each and every corner. Only the top line of actors got the good makeup while every extra just got a non-moving pull-over mask. OK, probably not a big thing on a low resolution 70s movie.
Following a series of Brent and Nova get hunted, captured, escape and get hunted again, we land in the nuked NY. All that was stuff the viewer doesn't need to see because we already know what happened and re-living it with Brent is, well, boring.
We discover a human civilization that is telepathic and praises a nuclear bomb as its God. And I can't help but thinking that this was the age of LSD and how much the writers did consume. Especially seeing the doomsday mass. It comes to a final showdown between Ape and Men that results in the activation of the doomsday bomb and a voice from the Off declares that Earth is destroyed. And my immediate thought is: "Finally !"
Now, to be fair, there are still the theme of how the Ape society mimics contemporary humans. You understand that this movie is aimed at the Vietnam war, you have the student protests f.e.. And the story is born out of the fear that a war like that could become the end of all, which cleary was what people were afraid of. You also see both sides making justifaction for their course of action and it's not difficult to see that both are wrong. There lies a wasted opportunity because all that time this movie favored action and shock moments over substance and story. Well, I'm expecting too much from the era. [/spoiler]

Anyway, if you want to watch all the movies, go ahead. But be aware this is a massive drop from the first one. If you are just a casual viewer that liked te first and wants a sequel you better stay away.