Goofs

Panties suddenly appear on Niki's fully nude body in the peep booth. This goof is seen on old video and cable un-matted versions. (On DVD, the portion showing that Niki is wearing panties is properly cropped out and doesn't show.)

In close-ups of Jake driving, filmed through the windshield of the car, the rearview mirror has been removed. This is fairly common and is done to provide a less-distracting shot. However, in shots of the car seen from outside, the mirror is still in place. (This is also a revealing mistake.)

When Jake has returned to L.A. and fires his detective, he creates a list of establishments to do his own research and that evening and drives around visiting places on his list. The first place he visits has a street number of 739 (visible in frame) but in looking at address detail in the long shot of the list itself, there are no references to a street number of 739 anywhere.

When George C. Scott and Season Hubley interact in "Les Girls," it is implied that the establishment is located in Los Angeles, as they talk about going down to San Diego. The actual "Les Girls" is located in San Diego.

The interior scenes in Grand Rapids of Jake's Calvinist relatives smoking and of Kristen's room with Star Wars: Episode IV - A New Hope (1977) and other 1970s memorabilia and a peace sign is so inconsistent with Calvinist upbringing of children. (This is not a goof really but an opinion. George C. Scott's character was a single parent who was not as uptight as some of the other Calvanists, like the uncle who forbade the kids to watch the Christmas special. Also, as a single father, he wasn't totally in control of his daughter. Most importantly, "Star Wars" was a movie geared for young people, and is NOT considered sinful.)

Jake flies to San Diego, then is shown driving the same car he drove in Los Angeles. This does not appear to be a case of using a Los Angeles location as a substitute for San Diego. Judging by the lampposts along the street, they actually transported that car from Los Angeles to the Lower Broadway area of San Diego to film the scene. Continuity or Revealing Mistake, it is an immensely huge error that requires significant logistical effort.

Jake takes Kristen directly from the back room of a nightclub to the back seat of a squad car. Jake and Kristen were both inside the nightclub before any police arrived on the scene. Nothing in the film explains why Jake and Kristen just walk out and get into the police car.