When the wife's body is first placed in the car, it looks like a black 1959 Buick. When the car is pushed off the cliff, it looks like a gray, late 1930's model.
When Paula goes to the apartment to see Byrd in # 303, the bell is on the door trim. However, when Perry takes Tragg to the apartment, the doorbell is located on the wall and not on the trim.
When Byrd films Houston pushing the car off the cliff, his camera is tilted up at about a 45-degree angle. But the image through the viewfinder and the pictures he later shows to Houston and to Paula Wallace have a level perspective instead of from a low angle looking up.
Charles Houston pushes a fairly late-model black Buick (with his wife inside) toward a cliff. However, the car that actually goes over the cliff is anything but the car viewers saw him pushing toward the cliff; instead, it appears to be an automobile from the 1930s or 1940s.
A scene set in a Southern California forest includes footage of a nonnative deer.
Byrd locks Paula Wallace in the apartment containing Houston's dead body, but apartment doors cannot be locked from the outside so that people inside cannot get out in case of a fire or other emergency. The doorknob would contain some sort of inside unlocking mechanism.
The murder victim was killed with a .32-caliber bullet, but the murder weapon left lying near the body was a Smith and Wesson .22 Kit Gun.
Roger Byrd films a car being pushed off a cliff. When the car tips over and starts its descent, the viewfinder image cuts to a long shot taken from a vantage point far from where Byrd was standing.