Trivia: Linda Harrison, who portrayed Nova in the original Planet of the Apes and its sequel Beneath the Planet of the Apes, has a cameo appearance in this movie as one of the people inside the rolling cage as it's being taken into the city. She is seen standing next to Mark Wahlberg, shaking her head when he asks her a question.
Trivia: Makeup artist Rick Baker has a cameo appearance in this movie. He appears as one of the apes in the city who is seen smoking from a water pipe.
Trivia: In order to star in the film, Tim Roth had to decline the role of Professor Severus Snape in "Harry Potter and the Philosopher's Stone" (2001). That role was eventually given to Alan Rickman.
Trivia: There are some lines in this movie that were famous lines from the old Planet of the Apes. They are "get your stinkin' hands off me you damn dirty human" (previously "Take your stinking paws off me you damn dirty Ape.") and "damn them, damn them, damn them all to hell" (previously "damn you, damn you, damn you all to hell").
Trivia: Charlton Heston, who was the president of the National Rifle Association at the time, is the only ape with a gun.
Trivia: The symbol of Ape City (the open circle with the vertical line) represents the Oberon, their origin.
Trivia: Thade's father was played by Charlton Heston, who played the main character, Taylor, in the original Planet of the Apes.
Answer: To prevent anyone else from learning that Leo came from space. After Pericles' ship crashed, there was a prophecy of a second coming of Semos, the founder of Ape civilization. Thade wants to kill all humans, so if anyone found out, it would be considered a sign and the council might consider making peace with the humans.
Captain Defenestrator