19. The T-Rex
Appears in: Jurassic Park (1993), Jurassic Park: The Lost World (1997), Jurassic Park III (2001)
Scariest moment: A jeep's rearview mirror shows the standard "Objects in mirror are closer than they appear" as the T-Rex's face roars up close and personally into the mirror.
Growing up, most little boys scour books and visit museums to learn all about the dinosaurs that once ruled Earth, and, obviously, the Tyrannosaurus Rex commands more attention than any other dinosaur. So when Steven Spielberg's blockbuster adaptation of Michael Crichton's novel Jurassic Park debuted in June of 1993, kids everywhere demanded that their parents bring them to the nearest movie theater. The thought of seeing a T-Rex in action was too awesome to quell.
But then kids actually saw the T-Rex in Jurassic Park, and nightmares ensued. Wisely, Spielberg and screenwriter David Koepp kept the "tyrant lizard" entirely evil, complete with a magnificently staged emergence involving the Tyrannosaurus, a few jeeps, some petrified humans, and a doomed lawyer sitting on a crapper.