After they literally blew up the Earth in the previous movie you wonder were there might be room for a sequel.

[spoiler] This on starts with a surprise (that is if you hadn't seen it before) as the space ship coming back to Earth is manned by Apes. Here you have to be, once more, a bit lenient. Not once in the previous movies was there any mention of Taylor's ship being salvaged or even studied by the Apes. On the contrary they believed flight was not possible and it's a leap to come to the conclusion they build a fully fledged rocket only a short time later. You also need to buy in that by sheer conincident went back through time to land on Earth in the, then, present.
As I mentioned those story gaps where present in the previous movie, too. But whereas that one never presented a tangible story this one does much better in that regard. I think the idea to do basically a one-eighty was really good. Althought it might also have originated from budgetarry reasons as doing a film in the present was much cheaper.
The story itself is cut in largely two parts. The first is light-hearted, humorous. Althought I have to admit the contrast in how Zira and Cornelius where treaded, as oposed to how Taylor was at first, was a bit too much. It seemed they wanted the humans to look good, even the President was very benevolent towards the Apes. That part actually felt off and I feared for a full comedy to take place.
All that takes a stark turn towards a darker tone when the President's Adviser, a guy by the very German sounding name of Dr Hasslein, takes action. He fears for the dominace of mankind and thinks he can prevent a futrure where men is no longer superior. There is a lot to be interpreted into that but I'll leave it at that.
Anyway, we learn from Cornelius how everything started, something that had been mentioned before but not in such detail. How the Apes rose to dominance. Which only fuels Hasslein's hate and ambition of preventing that from happening. The following hunt results in the tragic finale and you're left with a bad taste in your mouth as once more men is shown as the evil species. Not all of them of course as there are some doing good.
The second half is what propels the movie far above average for me. There is a lot of meaningful dialogue that deals with the thread of how men is working towards his own extinction and it's not hard to buy into that. Sadly, I might add. [/spoiler]
In summary this movie is much, much better then the second.