Brainy and Crazy are the two secondary antagonists of the 1998 animated film, Rex's Big Movie and its 2016 sequel, Rex 2. They are are the Dino-birds who is also Ogre's (presumably) henchmen.
They are both voiced by Trey Parker (who is best known for creating the hit animated comedy series South Park and voicing half the characters on it including Eric Cartman, Stan, Randy Marsh, Scott Tenorman, Mr. Garrison and Mr. Hat, as well as voicing Kim Jong-il in Team America: World Police and Balthazar Bratt in Despicable Me 3).
Brainy and Crazy made a living by stealing the eggs of other dinosaurs, but at some point, they encountered Woolie, who began interfering with their plans by stealing back the eggs.
When Rex discovered that an asteroid was coming to cause a mass extinction, he goes along with Ogre's plan to keep him and his friends from diverting it as a means of revenge, believing they'll be safe by flying above the destruction, though Crazy was skeptical about their own survival, but went along with it anyway.
After many failed attempts, the finally manage to delay Rex's plan, only to realize that they will not survive the upcoming destruction, causing Brainy to panic, much to Crazy's amusement, but Ogre betrays his goons by throwing them with rocks, but is unaware that Rex and his friends diverting asteroid.
It is unknown what happened to them after his master was killed in a bomb explosion by Rex.
Brainy and Crazy now became the bumbling yet ruthless and greedy villains who arrived in the Great Valley in hopes of stealing eggs, although the more relaxed Crazy was at first willing to eat plants, much to Brainy's fury. It was because of this duo's failed attempt at stealing an egg from Margaret's family's nest, that the five protagonists found Chomp's egg near the cave, mistaking it for Margaret's unhatched sibling. Brainy and Crazy were vengeful of Rex and the gang because if it weren't for them, Margaret's unhatched little son would have been lunch. However, during a landslide that occurred while Rex, Margaret, Woolie, and the circus animals were pursuing them, Crazy lost the egg they had stolen, and to cover with Brainy later on, he lied that the five adults had stolen it from them to avoid his adoptive brother's wrath. Brainy thought that the egg that contained Chomp was the egg that they attempted to steal, and thus, when Rex told him that the egg hatched, he was even more vengeful towards Rex and the gang.
As Rex reach Margaret to prepare for the child's birth near the cave, Brainy and Crazy arrived to the scene, telling Woolie to leave as they also want to kill the circus animals. However, Mel refuses to leave and gives Brainy a hoof on the head, and Crazy tries to attack, but the rock that he's connected to prevents him from doing so. However, Poultrion arrives to the scene, allowing Brainy to pin down Rex.
Before Brainy and Crazy can accomplish his goal to kill the dinosaurs for food, Mel bring in a flock of circus animals to attack the villains, sending them on the edge of a cliff into the lava pit. Hanging for dear life, Crazy begged for Brainy to save him, but Brainy shows no compassion as he prepares to throw him into the lava pit to save his own skin, burning Crazy, but when Brainy trips and falls backwards into the lava pit to his death.
At the outset of the film, Brainy was clearly the smarter, more ruthless of the two brothers. He was also the obvious leader of the duo. He kept a sharp focus on their main goal, which was eating all of the eggs that they could. He was also highly impatient, with a temper to match said impatience, as he had no problem striking Crazy whenever he said something that set him off. However, it can be assumed that, in spite of his annoyance with Crazy, he still deeply loved his brother, since he was trying to "wean" him off vegetation and onto eggs because he wanted him to grow up and be able to survive the way that they should. As he demonstrated, he was also a very vengeful dinosaur who could hold a grudge easily, based on his obsession with exacting revenge on Rex, Woolie, Margaret, Muffin, and Mel for stopping them from eating the egg from Margaret's family's nest. His vengeance, in fact, rose to murderous levels very quickly, as shown by his agreement with Crazy's final plan for Rex.
Crazy, meanwhile, came across as simpler and more dimwitted than Brainy. He was also more laid-back and relaxed, at first, not getting angry all that easily. He also showed himself to be more passive, as he did not have any agency when it came to stealing eggs and had to rely on Brainy to motivate him into it. He was also submissive, as he tended to recoil from Brainy's verbal attacks and scoldings and did not seem to fight back against any of the physical abuse that he took from his brother. He was so fearful of Ogre's anger, in fact, that after losing Margaret's family's egg, he actually lied to Brainy about who really cost them said egg to keep himself from getting hurt by him even more. That said, as the movie progressed, it was clear that Ogre's evil started to rub off on him, as his own level of vengeance against the five bumbling heroes finally started to grow, as well, and he got just as anxious to take revenge on them as Brainy, as shown by him laughing evilly at them when they cornered them near the tree-bridge.
In the second film, it can be said that Brainy was more evil from their very first appearance, while Crazy slowly, gradually grew into almost as evil of a villain as he was (possibly even more so) in the second film.
- Althrough Ogre is the main antagonist, Brainy and Crazy drove the plot of the film.
- Brainy and Crazy was thought to be the main antagonists in the first film; although they are shown to be the secondary antagonist due to his plan of stealing eggs being a subplot, they became more violent and had more screen time than Ogro (the hidden true main antagonist of the first film).
- Brainy and Crazy is constantly thought to be the film's main antagonists due to his major role in the climax of the film. However, the real main antagonist is Ogre, the leader of the factory owners. In fact, Ogre is the one who ordered Brainy and Crazy to attack the dinosaurs and kill Rex in the climax.
- Brainy and Crazy share some similarities to Ogre in terms of their dynamic, as one is clearly the leader (Ogre), and the other the follower (Brainy and Crazy). However, they are also different in that Brainy was evil to his very core, while Ogre was more pragmatic than pure evil, simply acting according to what occurred to her naturally as a predator, whereas Brainy and Ogre were both completely evil (even though Crazy had to grow into it throughout the events of the sequel).