Continuity mistake: At the start of Bev's final sing-a-long before the credits, she steps to the front of the stage with her guitar in hand. In the very next shot, when she starts to sing, a microphone magically appears in front of her. (01:42:49)
Continuity mistake: When Howard and Phil are being chased by cop cars in the ultralight, after Phil says "Trust your birdness - fly!", we see a front-facing shot that shows a cop car pulling up to the right of the ultralight. In the very next shot, no cop cars are even near them, just following. (01:19:55)
Revealing mistake: Before the car pulls up by the diner, after smashing a billboard, skidmarks from previous takes are visible on the ground.
Revealing mistake: When the Overlord extends his arm outside the truck, lights up and electrocutes a cop the shadow that his arm casts is not real, but FX made. Problem is, his arm does not cast any shadow on the truck for a couple of shots.
Suggested correction: Again, watching the movie right now. His arm is indeed shown as a reflection.
Visible crew/equipment: When the cop commands Overlord to turn off the engine, a big black tower from the filming equipment is reflected on the front part of the truck. It is not visible in the wide shots of the place.
Revealing mistake: During the ultralight chase, a police car drives up a hill and overturns. The metal plank underneath to allow for the stunt is visible.
Continuity mistake: After Howard beats the punks' asses, Beverly's umbrella briefly disappears from her bag. (00:11:23)
Continuity mistake: Right before the bad guys place Howard on the counter his drink disappears from the counter and reappears 30 cm away to allow for the stunt.
Continuity mistake: Outside of the museum a bunch of kids reach out and touch Howard. The hands appear and disappear randomly between shots.
Continuity mistake: At the bar, while standing on the counter, Howard punches a guy with a hat on. Then he punches him again and the hat is gone, only to reappear in the close-up.
Continuity mistake: When Jenning destroys the Ketchup bottle he only breaks the upper part while the label remains perfect. A shot later the label in the lower part is broken in two.
Continuity mistake: When the Overlord is about to explode the Ketchup and mustard bottles, the Ketchup cap is either loose or tight depending on the angle.
Revealing mistake: When the microlight is about to fall into the lake next to the lab, Howard's POV shows a straight road ahead. However, a shot later the microlight rises from an obvious ramp hidden between bushes which results in a more comedic crash.
Visible crew/equipment: When the movie ends and Howard and Beverly dance onstage a mirror reflects the crew and cameras.
Revealing mistake: When Howard's chair is launched backwards, right before he crashes through the toilet room check for the black metal object underneath the chair where the mechanism to move the chair is.
Revealing mistake: When Jenning/Overlord sends a man flying through the window, the cable attached to his back is perfectly visible.
