Revealing mistake: When the car Howard Saint is tied to explodes, watch Howard's body - it's clear that he's been replaced with a hilariously obvious dummy. It's especially comical if you look at his legs, because it appears that the dummy doesn't even have legs inside of its pants given how they "wobble."TedStixon
Revealing mistake: When Frank kills Howard Saint at the end of the film, pay close attention when the cars start to explode. About a second-and-a-half after the first explosion, the camera cuts to a high-angle shot looking down at the cars exploding. Pay attention and you can see a lot of errors. For example, there are two cars (one red and one blue) on the right side of the screen that are teeny-tiny models and aren't properly blended into the background with blurry edges around them. Additionally, the three cars on the bottom left of the screen also have noticeable black lines around them. (Likely from a poor compositing job.) It appears the show was created with different miniatures layered over a background plate, and the various miniatures weren't properly comped into the shot.TedStixon
Continuity mistake: When Saint's men murder Castle's family, the man who tried to escape on the motorcycle is shot and falls off next to the motorcycle. The motorcycle slides and comes to rest with the back of the motorcycle facing the large deck and ocean. However, when Castle chases his wife and son, he picks up the motorcycle, and it is turned around with the front facing the ocean.
Continuity mistake: After Frank Castle climbs out of his flipped Pontiac GTO, Harry Heck walks up and points his shotgun at Frank. Frank points a closed switchblade knife at Harry and pushes the button, sending the knife blade flying into Harry's neck. When it switches back to Frank, there is still a blade on the knife, in the open position. After a cut to Harry, it switches back to Frank and the knife blade is gone.
Continuity mistake: When Saints's men are killing Castle's family, there is a shot of Frank and his dad shooting at one of the guys behind the barbecue stand. In one shot Frank and his dad shoot the salad bowl and most of the salad comes out, then in the following shot the salad has magically reappeared. (00:22:30)The-Immortal
Continuity mistake: When Frank crashes his Pontiac after speeding away from Harry Heck, Heck pulls up and walks up to Frank who is climbing out of his car. As he walks up, a piece of car is on the right side of Heck, but after Frank kills Heck, it cuts to an overhead shot and the piece of car is now on his left. (01:04:00)The-Immortal
Continuity mistake: When Frank is pulling down the gravestone with a chain, in the shot from the front, William's is to the left about a foot away and Maria's is to the right, the same distance. In the shot from behind the stone, there is another stone you can just about see on the right of the screen and it can't be William's because this stone, or something, is directly behind Frank's. (00:44:25)The-Immortal
Visible crew/equipment: When Howard Saint's men begin to chase after Frank's wife in their red 4x4, just after a couple of guys jump in the back, the camera pans forward to get a view of the driver. As the camera pans forward a boom mic with a large pole is visible in the reflection on the car. (00:24:20)The-Immortal
Revealing mistake: As the truck that Castle's wife is driving flips, you can see a burst of smoke or compressed air under the passenger side. Once the truck has stopped rolling, you can see a piece of U-channel bolted across the underside with a cylinder on the passenger side, which was used to help the truck roll over.
Continuity mistake: When Frank crashes his car and Harry Heck pulls up in his, note the distance from Heck's car to Frank's car, perhaps only a foot, yet when it cuts to an overhead shot, Heck's car is now quite some distance away from Frank's without anyone moving it. (01:03:50 - 01:04:25)The-Immortal
Continuity mistake: When Frank's family is being attacked, Frank and his father are inside the house fighting with some thug hiding behind the barbecue stand. At one point a shotgun shot is visible in the black metal lid on the left of the stand. In the next shot, the lid is intact, and then when the gas bottles blow up, it's shot again.
Continuity mistake: When Frank returns to his apartment after shooting the two guys in the lobby of the Saint building, the two tenants, the big guy and the small guy with the piercings fall out of the door and onto the floor. When they land the small guy has his left arm outstretched above his head, but in the following shot it is no longer outstretched. (00:50:25)The-Immortal