Plot hole: After running from the pirates, the two castaways almost stumble off a cliff. Unless they were running backwards, I'm sure they would have seen the cliff coming for a while, because when the camera zooms out you can see clear terrain for at least 20 metres until the edge of the cliff.
Plot hole: When Kalgan is torturing Lea, he says that he wants her father's countermeasures in case of emergency. But when she is rescued and finds out MacPhearson is a traitor who is working for Kalgan, Captain Devers is worried because MacPhearson knows all of the ship's countermeasures. If MacPhearson knows the countermeasures, then Kalgon does too, so there is no reason to bring it up while he is torturing Lea.
Plot hole: When Schaeffer, McFee, and Fergie drive to the Lapp farm to kill John, the car stops on top of a hill. Then it reverses a bit to be out of sight from the farm. But then the formerly careful guys get out and walk down the open road, sporting their guns like in an Italo western. (01:28:30)
Plot hole: Stuart establishes that there is only one of you and that when you travel through time you can repeat things, but it will be you and not your double that does it. But, at the end, when the Duke is going up the stairs and the uncle says "Where have you been...", the Duke is wearing the same clothes as the first time. Yet we see that he goes directly from the time portal to his house in the ballroom raiment of the later scene. Where did the old clothes come from?
Plot hole: When Henry rings Maurice's doorbell to give the bad news about Sarah's fatal illness, Maurice and Sarah are upstairs in the bedroom. Maurice approaches the window and looks down while we see Henry looking up in his direction. That he walks away without trying to make contact makes no sense. (01:13:45)
Plot hole: Nogerelli says to himself that the gap past Deadman's Curve must be 100 feet wide. How on earth was Michael meant to have made a jump of 100 feet (or even a few feet less) after both being slowed down by crashing through the wooden barriers and also by not having a ramp and therefore no upwards boost? He would have plummeted to the bottom.
Plot hole: In the makeshift morgue when Simon and Matthew first fight the vampires, Solina is shot and pinned to the wall with a large silver nail and remains calm and unaffected. However, moments later Marcus is fighting with Simon and grabs one of same kind of nails but must drop it when it burns his hands. It makes no sense that Solina had no adverse reaction to the nails at all when Marcus reacted so violently. (00:42:00 - 00:57:50)
Plot hole: In multiple scenes in the movie the starship is in a gentle rotation which allows 1G gravity on the ship. When the power to the propellant is cut the rotation stops and gravity is lost. Such a design for a starship doesn't make sense as the entire structure could be put in a continuous motion, as is indeed done with many probes today without requiring the continuous addition of power. Even if this design was chosen with part of the structure fixed and party of it moving around it still seems unlikely that the rotating part would come to a grinding halt within seconds (if it did, the friction of the structure would be huge, requiring enormous levels of energy to keep it moving) The only reason the movie chooses this unlikely design is to integrate the crucial shot of Aurora floating out of the pool when power is first lost.
Plot hole: Sarah breaks a mirror in frustration by throwing something against it. Then she buries her face in her arms and sobs. It remains a mystery how she managed to cut her hand so bad that it needed to be fixed with five stitches, as she isn't even seen picking up the pieces. (00:59:15)
Plot hole: Jamiel delivers Ali Baba's ransom note to Hulagu Khan by throwing a knife, and the shocked Khan and his guards look to the window. Since Jamiel does not duck away immediately, he should have been seen and identified immediately, but nothing of that sort happens.
Plot hole: Richard eventually manages to travel back in time by removing all the modern items from his room. But what about the spotlights above his bed? (00:31:40)
Plot hole: Catherine Zeta Jones says that she needs ten extra seconds after midnight to download the program that collects the billions of dollars from the international bank. In the movie at two different point, she states that after 11:00 PM the device she linked to the clock is gathering an extra 1/10 of a second every minute to allow for ten seconds at midnight. If you take a tenth of a second a minute for 60 minutes, you end up with only 6 seconds. 4 seconds short of the required 10. Some people say she only says "a fraction", but she explains the scenario twice. In one instance, she indeed says a fraction, the other time she definitely says 1/10th of a second, which is wrong.
Plot hole: When Wolf and Tony find Virginia in the Huntsman's tree house, she tells them that he chained her up, so she can't go downstairs and open the door from the inside. However, after Wolf climbs her hair and enters through the window, the two of them walk down the stairs without any chains stopping her. They couldn't have cut her free with the magic ax because Tony was holding it, and he was downstairs by the door.
Plot hole: When Dan is chasing after Carter to catch him and Alex together at the restaurant, there's very little chance he could have had any idea where Carter was going. He couldn't have told the cab driver to "follow that taxi" because in the time between Carter getting in a cab and Dan getting in a cab about 5 taxis drive past, so how he happens to end up at the same place is a miracle.