Character mistake: When Katie's husband arrives in town and confronts her on the night of July 4th, he says "I miss you Katie." He does not know her name to be Katie as that is the name she created when she came to town. He is married to Erin.
Revealing mistake: Early on, after Clary blasts the demon with a homemade explosion that blows a huge fireball across the kitchen and blasts out the window, there is no sign of anything being burned, not even the curtains. The kitchen is only in a slight shambles and there are small fires burning in isolated areas that never spread or char anything.
Continuity mistake: In the scene where Heather runs through the fairground she grabs onto the back of the Ferris wheel seat and is taken up in the air. Leatherface throws the chainsaw at the cop and the next shot shows Heather coming back down the other side of the Ferris wheel. But she should be on the inside of the carriages as it just spins round on an axis. These kinds of wheels don't "twist" at the top otherwise the rider would just be staring at the inside of the wheel the whole time.
Factual error: In this relatively low-budget but extremely well-produced 2013 science fiction film, a 6-man crew travels from Earth to Europa (one of the moons of Jupiter) to search for traces of life in the vast oceans beneath Europa's icy surface. One of the astronauts dies in-transit, leaving 5 crewmembers to complete the mission. When the large "Europa One" interplanetary spacecraft arrives at its destination, all 5 surviving crewmembers descend in a small landing craft to the moon's surface, leaving the Europa One spacecraft in orbit, totally unmanned. This is an inconceivable factual blunder. The narration plainly states that this mission picked up where manned lunar missions of the 1970s left off; so, many of the same protocols are in place. Just so, no manned space mission would ever abandon the primary space vehicle in orbit, placing the mission at risk by sending the entire crew down together in a landing party. At least two astronauts should have remained aboard the orbiting Europa One just in case the landing mission went sideways (as it does in this film).
Continuity mistake: Radha Mitchell is giving a press release at the beginning of the movie. There are many microphones in front of her in rows. In the front row, from her left, are orange, black and blue microphones. In one shot from the front, another black microphone appears next to the blue one. (00:03:35)
Other mistake: During the climactic gunfight Jay Swan retreats to his car. Using his binoculars Swan looks to the left and slightly rear of his car to see Pete Bailey (who is shooting at him with a high-power rifle). Bailey fires a shot at the car and the bullet strikes the front windshield (an impossibility from that angle). (01:48:00)