Continuity mistake: Near the start, when Ellie runs to the tire swing, she does a cartwheel and loses her hat, but in the next shot, her hat's back on her head. (00:04:05)
Continuity mistake: When Alice and Mark are collecting all the sheets from the floor, Alice looks at a sheet about Amanda Krueger. Then in the next wide shot as her dad calls for her, all the sheets are in a pile to her right. Then in the following closeup, she starts picking up sheets of paper from all around her. (00:53:35)
Continuity mistake: In one scene we are looking at a shopping complex known as Greenspring Station which Nina is being chased through. Somehow she winds up being chased through a K-Mart. Anyone familiar with the Baltimore area, where the movie was shot, knows for a fact that there is not a K-Mart anywhere near that ritzy section of town.
Continuity mistake: When Fletch goes to visit Calculus in his shack, he knocks on the window and sees Calculus sitting in a chair, wearing boots. The next shot, as Fletch is walking inside, Calculus is now wearing socks and no boots, despite never having left the seated position, nor having had any time to slide his feet out of the boots. (00:35:55)