Continuity mistake: Right after Jay and Silent Bob run off the Good Will Hunting 2 set from the security guards, they run outside and Jay's jacket is tied around his waist. Then, they run into the Scream movie set and he has his jacket on. As soon as they run out of the Scream movie set, his jacket is tied around his waist again.
Continuity mistake: When Jay and Silent Bob first get into the van with the girls and Brent, Brent reaches out to squeeze Justice's thigh with his left hand, but as the the camera picks up the actual squeeze, its Brent's right hand squeezing her thigh.
Continuity mistake: Near the end when Jay and Silent Bob fight Mark Hammil, Jay takes out the double sided bong saber and takes a hit from it; you can see the plastic lightsaber part of the other blade in the corner of the screen. It's white and green.
Continuity mistake: During the last scene with Morris Day and the Time performing on stage, after Jay kisses Justice she makes "Kissy" faces at him. When the camera cuts, she is no longer doing so.
Continuity mistake: During the shootout at the end, J and SB are hiding behind the car and a shot pierces the car between their heads. In later wide shots, the bullet hole is missing.
Visible crew/equipment: When Jay and SB are kicked off the bus and are bitching about it, a boom mic is reflected in the back window of the bus.
Continuity mistake: In the scene where George Carlin is telling Jay and Silent Bob about hitchhiking, the pole thing behind them appears and dissappears from shot to shot.
Continuity mistake: During the scene where Brodie talks to Jay and Silent Bob about Bluntman and Cronic, he shows them a copy of Wizard magazine with a related article. On the right page is a picture of Holden and Banky. They then take this magazine and eventually show Holden McNeil the same article. The right hand pictures are different from how they were before.
Visible crew/equipment: When Ben Affleck is talking to Jay and Silent Bob in his 'Casa' near the start of the film, on the furthest shot you can see a guy or girl on the right of the reflection on the computer's coloured monitor. This is obviously a crew member because at one point, when Ben is talking, you can see the person moving around.
Continuity mistake: In the scene when Wildlife Marshall Willenholly joins the Utah Police in front of the Diner, the police cars move closer together and farther apart to allow for the marshall to walk from behind to in front of the cars.
Revealing mistake: When the girls are shooting at Marshal towards the end, in some shots you can see they aren't really pulling the triggers and that the muzzle-flashes have been added with special effects.
Continuity mistake: When Holden is reading the posts on moviepoopshoot.com, the right side of the browser window changes positions. It will change where the window takes up the whole screen, to where the window is smaller and you can see several icons to the right of the window.
Other mistake: During the credits of the movie, after Morris Day points to Jay and Silent Bob, there is an Asian guy jumping up and down at the far right hand corner. The shot switches back to Morris Day and when the shot goes back to Jay and Bob the Asian guy is wearing a light beige hat. The extra submitted this entry himself - he was wearing the hat during the shots. Then after several takes someone in costumes noticed it was a major logo ("No Fear") so he had to take it off. The shot was used before he had his hat on.
Revealing mistake: When the girls do their 'Entrapment' routine jumping through the lasers at the diamond vault, you can see them cut through the beams with their arms, legs, and hair.
Continuity mistake: In the scene where Jay and Silent Bob are getting busted, the cop is holding the pack of "wraps" in the air. When the shot changes so that Jay can pull down his pants, the cop's hand is down.
Revealing mistake: When Silent Bob is typing the message on the website about their revenge on the people who have bad-mouthed them, he just taps the last row of keys but there is a lot of writing put in the message.
Continuity mistake: Towards the end of the film when Jay and Silent Bob battle Mark Hamill, Jay cuts off Hamil's huge hand, and you see it drop to the ground, and you see his smoldering arm with no big hand. In the next shot when Mark Hamill is fed up and marches off camera, you see he once again has his huge hand attached to his body.
Continuity mistake: Near the end when Justice is talking to Federal Wildlife Marshal Willenholly after he's been shot by the orangutang, Justice's hand moves between shot. It goes from knee to floor and changes several times.
Continuity mistake: When Chris Rock's assistant brings him a cup of coffee, he hands Chris the cup, then the cup is back in his hand, then back to Chris' hand again.
Continuity mistake: In the scene where Jay and Silent Bob first meet Shannon Elizabeth and her friends, Eliza Dushku is wearing a necklace. Yet when they stop at the store she isn't wearing it. Then when they are back on the road she is wearing the necklace.
Factual error: The movie "Blunt Man and Chronic" was premiered at the El Rey theater. When Jay comes out he says "The party is across the street featuring Morris Day and the Time." However the location used for the club scene was actually inside the El Rey Theater.
Other mistake: After Jay and Silent Bob catch a ride in the van with the quartet of diamond thieves and Brent, they say they are the Kansas State chapter of SAAC and they are headed to the Provasik Animal Testing Lab (located next to the Colorado Diamond Exchange, so therefore most likely in Colorado). The Mooby's restaurant is located in Kansas City, Missouri (as stated on the sign visible when Jay wakes up from his Scooby Doo nightmare). The Kansas State University campus is located in Manhattan, Kansas, which is about two and a half hours west of Kansas City. If the diamond thieves are headed west, to Colorado, then why are they stopping to eat nearly three hours out of their way to complete their mission? Even though the thieves aren't really from KSU, Brent was their patsy, meaning that he wasn't in on their plot, and therefore must himself have been from KSU; he would have no reason to lie to Jay and Silent Bob, given he tells them the truth about their mission (as far as he knows).
Continuity mistake: When Justice is talking to the other girls (mainly Sissy) up at the balcony of the motel room, there are some clouds in the sky. However, between shots suddenly the sky is completely clear.
Continuity mistake: During the gunfight at the end Will Ferrel's and the vixen's model of firearms change a few times.
Continuity mistake: On the set of Good Will Hunting 2 Ben Affleck's spiked-out hair changes shape between shots.
Continuity mistake: Near the beginning of the movie when Jay and Silent Bob are in the comic book store talking to Brodie, watch the man who is leaning against the wall reading the comic book. (the one Jay teases while walking past) In one shot he has the comic, then a second later he doesn't, and finally a second later he has it again and walks away. [For anyone who has seen or owns the 2 disc dvd of the film, and has watched the second disc, it will have tons of deleted scenes, including one for this scene. It shows Brodie having a go at the man for bending the spine of the comic book, and smacking the comic out of his hand. He then walks off, the guys feelings is hurt and leans against the wall, and the film continues.]
Continuity mistake: Near the very end of the film, Jay and Silent Bob are going around beating up everyone who posted bad comments about them on the internet. When they beat up the guy in the convenience store, a bunch of items fall off of the shelf behind him. When the camera keeps cutting angles, you can see that the items are back on the shelf and in different order.
Continuity mistake: In the comic store, "Brodie's Secret Stash," if you press "pause" right when Brodie reaches for the Bluntman and Chronic comic book to show Jay and Silent Bob, you will see that he is right across a comic entitled "Cable." To the right of that is another comic, "Captain America," and if you can recognize it, to the right of the "Captain America" comic is a "Captain Marvel" comic. If you look behind Jay, you can see the same exact thing.
Factual error: Near the end of the film, during the big shootout scene, there are 2 girls vs. Will Farrell. If you play the movie in slow-motion, you can see that the guns the girls are shooting continue to shoot fire out of the barrel several times, even though the slide is locked back. When a handgun's slide locks back, the magazine is empty. How could they still be shooting when there are clearly no bullets left?