Overcoming fears of being caught, Bill and Jeff move the humans from the warpath of General Urko and his army. Will the two be able to help the people get to a new home before Urko catches up to them?

The Simian Senate convenes a secret session to discuss an event that could have direct effect on ape society - one of Urko's soldiers, returning from a journey into the Forbidden Zone, babbling about intelligent humans.

During an archeological dig on an ancient ruin, Cornelius uncovers an ancient, human-made book entitled 'A Day at the Zoo'. Needless to say, the images and words inside could lead to much trouble for man and ape alike....