Other mistake: When Stephanie (the kid's mom) gets sprayed with mud by the bus, it is accelerating as much as it can in reverse. Why would it accelerate so much in reverse if it's trying to avoid falling down the hill?
Continuity mistake: When Gordon and Benny are in Stephanie's apartment with James, you can see the clock behind Benny, but a few of shots later the time has changed to being earlier.
Factual error: When Stephanie gets in the back of the zoo wagon, she discovers a zebra back there. Then all of a sudden the zebra toots and the flames go way out of the back of the trailer. In real life that wouldn't happen because the gas doesn't come out of your rear end fast enough to have that happen.
Character mistake: At the FBI facility, Agent 11's handler buckles the collar on the dog's neck. Later, when Gordon has put the collar on and tries to get it off, he's trying to pry it off. He just buckled it on not two minutes earlier. He's stupid, but not that stupid.
Revealing mistake: In the beginning, Gordon is driving his truck and "drinking" something out of a thermal mug. He's be-bopping around so much it would have spilled all over him. If you look closely, you can see he's not really drinking at all.
Continuity mistake: In the pet shop, Gordon gets all wrapped up with plastic wrap. Just a few short scenes later it's gone. There's no way he could have gotten himself out of it in that amount of time. Also, the "plastic" fishbowl shatters - plastic fishbowls like that are not that rigid and would not break like that. Add to that the "piranha" tank is obviously a bubble line at the back of the tank - you can see the bubbles come up when they reach the fishnet in.
Continuity mistake: During the end of the movie, spot is in the park again, and when he looks at the bad guys, he has a collar on and then when he looks back, it is off. This happens for a minute or two.
Continuity mistake: Towards the end, the mail truck has a reflector hanging outward on the driver side. Later scenes, it's back in place.
Continuity mistake: When the boy gets a call from his mom, she is far away from the truck. When it spits mud up, she is right next to it.
Visible crew/equipment: At the pet store, when Spot stands on his hind legs in order to push the shelving unit onto Gino and Arliss, the arms of a crew member can be seen pushing the shelving unit.
Continuity mistake: When Gino and Arliss are given the contract to kill Agent 11, note the distinctive pattern on the shirt Arliss is wearing - particularly the collars, which keeps changing even within the same scenes. Though the actor's wardrobe consisted of black shirts of the same style, their patterns varied. For example, during the scene at the pet store there are at least three different patterns seen on his shirt. The same thing happens again later with a different shirt Arliss is wearing, after the scenes of Gino and Arliss at the dog training facility.
Continuity mistake: When Gordon tastes the bran cereal with soy milk and prunes, the cereal box is on the table beside the soy and regular milk containers, but when he's gagging by the sink the cereal box has vanished in the shot facing James, and then it reappears. Things on the table change position as well, such as the soy milk turning itself around.
Continuity mistake: When Gordon fixes himself the bowl of bran cereal with soy milk and prunes, he places the orange cap back on the soy milk, but when he tries to eat the cereal and spits it out, the soy milk cap is gone (the gallon of regular milk has a pink cap behind the capless soy milk). Then it's back on the bottle, before it's off and back on again.
Visible crew/equipment: When Stephanie gets into the van that's headed to the airport, the reflection of the cameraman and camera can be seen on the window when Stephanie shuts the door. (00:18:10)
Continuity mistake: Tyson, the dog on the chain, escapes and snaps the chain right in the center. When he reaches the tree, the remains of the chain are gone.
Continuity mistake: In the opening sequence, the driver's door on the mail truck is wide open. When the protagonist arrives at his destination a moment later, the door is closed.
Revealing mistake: At the beginning of the film when Gordon is delivering the mail to Spike's house, Spike gets loose and chases Gordon. Gordon runs to a tree, and somehow he flies all the way up to its branches.
Continuity mistake: In the first scene the little boys mom is covered in mud then it switches to Gordon then it goes to her again and she is hardly covered in mud.
Continuity mistake: When Benny takes the Polaroid photo of Gordon, James, and Spot, their positions differ in the resulting photograph.
Visible crew/equipment: When Spot bites Gordon's helium filled bubble-wrap, Gordon knocks over Gino and Arliss as he flies across the aisle, and before the shot cuts away we can see a crew member at the left side of the screen just as Gordon passes him.
