Corrected entry: When Randy gets shot by Billy, he spins around on the spot yet in the next shot he's flying through the air and lands on the table.
Corrected entry: In the beginning, when Billy is leaving Sidney's room, he climbs out the window and walks away, which isn't possible because all the roofs on the house are slanted and it's at least a two story house. If her bedroom's on the ground floor, why the next night does she go upstairs to get to her room?
Corrected entry: As Casey's parents walk into the house and the killer holds the knife above her head to stab her, notice the amount of blood. It is insinuated that he continues to stab her, yet later, when the mom hears her on the phone, the killer raises the knife again to show that no more blood has gotten onto the knife. Kinda weird that the knife seems so clean when Casey's body is completely butchered and bloody.
Corrected entry: In the part where Billy and Sidney are in Stu's parents bedroom, after they've had sex, the killer comes in and stabs Billy. Watch the killer in the background after he stabs Billy - notice that there is no blood on the knife and the killer wipes the knife blade off anyways. Then there's a shot of Sidney, and then it goes back to the killer. At this point in time, there is now blood on the knife and he then wipes the knife blade off again.
Corrected entry: Sydney locks her front door with a chain lock when she's on the phone with the killer the first time, but when she opens it after Billy comes over the chain lock is gone.
Corrected entry: Before Sidney invites Billy up to her room, he is wearing a blue shirt with a pattern on it. Yet, in the next scene (in her room), if you look closely, you can see that the shirt's pattern has changed.
Corrected entry: In the scene in Stu's kitchen at the end, when Billy has just been stabbed by Stu, Stu gives him the knife and is saying to Syd, "Everybody lives but us." When he says that they'll live because they have to plan the sequel, he is gesturing with his hands, with his pointer fingers pointed up. As he's saying, "'Cause let's face it baby, these days, you gotta have a sequel," his hands go in and out of the frame four times. Just as he says "these days," he has his middle finger up on his left hand instead of his pointer finger. Obviously deliberate on the actor's part, but pretty funny.
Corrected entry: (SPOILER)This may be an actual character mistake rather than a goof, but when Billy reveals that the "blood" on his shirt from when the killer "stabbed" him was actually corn syrup, he also has himself stabbed for real, to corroborate his story. But the problem is, it's the same shirt (as demonstrated when he licks some blood off of it and explains it was corn syrup.) So how would he have explained how corn syrup got onto his shirt while he was fighting off a killer?
Corrected entry: When Sidney is waiting for her friend, it's 7:15 and it's dark out. But later, all the stores are closing because of a 9:00 curfew, and it's light as day.
Corrected entry: Just after the curfew has been set, Tatum and Sidney go to the store, you can see a reflection of Ghostface but, surely the shopkeeper or anyone would notice a man walk in dressed head to toe like a serial killer with a ghost mask?
Corrected entry: When Sidney goes back into Stu's house after the killer tried to catch her in Dewey's car, she takes the gun out of Dewey's holster. The ends of her hair are wet with blood. But after she discovers that Billy is still alive after being stabbed, she goes over to him to help him up. The ends of her hair are completely dry.