Randall is mean, ruthless, and self-centred he is also sneaky, selfish, cunning and crafty.
Randall has eight legs and has the ability to turn invisible (as well as wall-crawling). He can also manipulate his colors like a chameleon.
Randall appears in the prequel as Mike's new college friend and roommate, but he joined the egotistical team known as Roar Omega Roar, who are against Mike. During the climax of the film, after he lost to Sulley, he glares at him saying "That's the last time I lose to you, Sullivan!", then went on the become Mike and Sulley's new enemy ten years later in the original film.
He first appears tricking Mike Wazowski after he plays with his locker door. He reveals himself and scares him. He mocked Mike after that, Mike told him that he wasn't scared but had "allergies", much to Randall's annoyance. He then goes to the scare floor along with James P. Sullivan and the other monsters. Randall, alike the other monsters, goes into his door and scares a kid. After he left the door, he noticed that Sulley is still on top of him on the scare record. He then glares maliciously, and yelled at Fungus while requesting him for another door. Later on, he briefly becomes the new scare leader with a crowd coming nearby him smiling. The crowd went to see Sulley after he beat Randall again. Randall then threatened to kill Fungus if he doesn't see a new door in his station in five seconds.
After finding out a child went outside of her door and went to Monstropolis, he reveals he was trying to find her while staying up all night in the bathroom to Fungus. He kidnaps Mike in Boo's room, thinking it was actually Boo. He and Fungus invented a new trap called the Scream Extractor. He later gets a shocked look on his face when he kidnapped Wazowski instead of Boo. He locks Mike up in his trap, After Sulley rescued Mike and put Fungus on the trap instead, Randall plugged the plugin to the Scream Extractor back in, and gets shocked again when the Scream Extractor worked on Fungus, giving him enlarged lips.
It is later revealed he made Mr. Waternoose betray Mike and Sulley by sending them to the Himalayas, and then they took Boo to the Scream Extractor. He and Waternoose argue about scaring and tells him Sulley got what he deserved. Mr. Waternoose told him he was twice scarier than Randall will ever be, to which Randall glared and growled at him. After Sulley broke the Scream Extractor with his strength and threw it at Randall, Waternoose, and Fungus, he picked Boo up and let her out of the trap. Randall has then whipped Sulley with his tail, telling him that he didn't know how long Randall wanted to hurt Sulley. He strangles Sulley after Mike returns. Mike threw the lemon snowcone at Randall, with Sulley punching him after that. He, Mike and Boo fled away for their lives. Mr. Waternoose in an angry mood told Randall to get up and there can't be any witnesses, Randall agrees with him while glaring at him. He then chases Mike and Sulley for Boo, He takes Boo away from Sulley, knocking out the door the two were holding onto. However, the two survived and went on to find him and Boo. Sulley jumped into a door, then almost got knocked off the door. Randall insults him while trying to kill him. Before he kills him, Boo brutally beats him up. Sulley gets back up on the door, and then strangles Randall. He tells him that he is out of the job. He then sends Randall to the human world, getting beaten up by a hillbilly family in a trailer. Mike then led the door down to the ground, getting broke. Despite this, however, Randall has survived.
- Randall is #27 in the Top 30 Disney Villains list.
- He is the first Pixar villain to be physically fought, the first being Stinky Pete.