Goofs

In the car chase, before the taxi hits the loader with the huge steel pipe, the cab driver ducks down sideways on the front seat. The next slow motion scene shows the pipe crashing through the taxi windshield. That segues into a scene with the taxi driver again sitting up and looking horrified before the crash. And finally, it goes back to a scene with the pipe having crashed through the windshield.

The handwriting on Tanner's sign changes between shots.

In the pool house fight, the exterior clip of the baseball bat smashing the window is used twice.

When Tanner finds the fake dog head in the refrigerator, the refrigerator door is open and closed in alternate shots.

American CIA agent Fassett states that Tanner will need to sign the Official Secrets Act. There is nothing termed the "Official Secrets Act" in the United States. The OSA is a term used in the UK, Australia, New Zealand, and other Commonwealth states.

During the closing credits we can see that the soundtrack is released by a label that goes under the name of Varese Saraband. The name of the label is actually Varese Sarabande, with an e in the end of the second name.

When Tanner goes to the airport, we hear jets taking off and see a sign revealing the place to be the Oxnard Airport in Ventura County. In real life this is a small airport with no facilities for passenger jet takeoff.

The surveillance cameras installed in the Tanner house each have a red light to indicate that they are working. Surely a camera for secret surveillance would not have a visible indicator for all to see.

When Tanner is warning the others to get out of the camper, he writes "Get out now". Richard is reading it aloud as "Get out of the camper now".

While Tanner is speaking with Fassett in the kitchen on the video screen, a technical glitch occurs when the rest of the Osterman friends enter without warning and the screen will not turn off, forcing Fassett to fake a weather report to cover while the men are there, during which he intends to use the term "barometric pressure", but mispronounces it as "baromotic" the first time he says it.

In the kitchen scene after Ali and the Tanner son are kidnapped, Ali refers to the boy as 'Steve', which is supposed to be the character's name according to the closing credits. But the actor's real name is Christopher, and he is referred to as 'Christopher' or 'Chris' numerous times throughout the movie. Note that it may have been challenging for Meg Foster to remember to refer to him as 'Steve' since he is her real life son.