Audio problem: When the children run out of the garden, the girl is screaming, but her mouth is not open.
Continuity mistake: In the woods on the island, when Edward first meets Sister Willow, he is about to close his sports coat, and in the next shot of him, the sports coat is buttoned up. After a quick shot of Sister Willow, in the next shot of Edward, his coat is entirely unbuttoned and open again.
Continuity mistake: In the opening scene, two people are dragging a coffin through the desert. After first seeing only their boots, when we see the two guys, the one wearing a white shirt is on the left, and the one with a red shirt on the right. But in the very next shot their positions have changed, now the man with the white shirt is on the left while the one with the red shirt is on the right.
Deliberate mistake: When Hellboy is attacked by the spider-lady, as the spiders begin to descend on him to steal the sword, you can easily tell that some of the shots of the spiders coming down are repeated 2 or even 3 times, and simply flopped horizontally to appear different.
Continuity mistake: When the little girl goes to the lunch wagon you see a bottle of apple juice behind her shoulder. When she walks away the bottle has been slightly turned and see can see more of the label.
Continuity mistake: When they're travelling in the coach, wideshots of them driving show them driving through deserted countryside. But in shots from inside the coach you can see the roofs of houses and telephone poles passing by.
Visible crew/equipment: A boom mic is visible at the top of the screen in one of the alternate endings where a mortician comes to get the body of Billy from the coroner.
Continuity mistake: When the monster puts down Hanso after she tries to escape, you can see her footwear is completely dirty, but in the next shot where the monster's tail uncoils itself from her body, you can now see the pink and white of her footwear that you couldn't see before.
Revealing mistake: When Zoe is getting killed she is spitting out blood from her mouth. Everything is ok with that, except she spits some of the blood on the camera right before she is thrown over the balcony.
Continuity mistake: When Sarah is in the library, Kate comes and leans on the table next to her. When we first see her close up, her ponytail is dangling by her head, it zooms out and the ponytail is on her back, again it zooms in and is in front of her face, zooms back out and it's on her back again.
Factual error: The guy who is invisible is ran down by a car while running after the cop and the scientist. He is shown getting up covered in blood. Everything about him is invisible which includes his blood. It shouldn't have been visible after the accident.
Continuity mistake: When the guy who swears way too much is pointing a flamethrower at the two other characters in the garage, he's holding the flamethrower nozzle in his right hand. But when he goes to roll up his left sleeve to show them his arm, he uses his right hand, and it's a direct sequence cut (note the left hand is visible in the same shot and is not holding the flamethrower). After he rolls his sleeve up, he's holding the flamethrower nozzle in his right hand again.
Continuity mistake: Right after Karen bites her father's neck, a bandage is placed on it. Immediately after this, Gerald fights his way to the house and they let him in. For several shots, there is no bandage, wound, or even blood on the father's neck while Gerald is explaining what's been going on. Then suddenly a close-up of the father shows that the bandage has re-appeared without anyone putting it there.
Audio problem: [Blu-ray] When Mandy goes to wake up Red and Chloe, she says: "Hey! Hey, we need to get up, OK? Come on." The last two words were missed from the overdub, are not heard and are also missing from the subtitles. (01:08:15)
Revealing mistake: In the scene where the group of unlucky virgin sacrifices make it to the Minotaur's sleeping chamber and are banging on the door trying to get out, one of them is gored and lifted into the air. When this happens you can see the harness and wires (the cables are about 1/2 an inch thick and black, one either side of the body). In the same shot the clothing of the gored victim is bunched up over the cables also. (00:47:40)
Revealing mistake: When Phoebe is looking at herself in the mirror, she's trying to find out why she isn't attractive enough for roles. When she takes her bra off and inspects her breasts, it's painfully obvious that that is not her real torso, as her head kind of bobs around in a strange fashion, showing that her face/head was superimposed onto another woman's body.
Continuity mistake: Breakfast scene - the mom walks past a plate on the table with toast and pancakes, she gives her husband his eggs and suddenly there are two sunny side eggs on the plate as Rachael sits down. Mom then brings two sunny side up eggs and puts them on Rachael's plate, and the 2 eggs that were there before have vanished. (01:20:35)
Visible crew/equipment: At the very end, when Ashley Judd and Michael Shannon set themselves and the room on fire, look very closely on the left side of the screen and you'll see someone who looks like he has some equipment on and is observing the fire.