Goofs

In the end-of-film chase scene, Santiago's blue car skids to a halt in the surf with the front facing the ocean. In all remaining scenes, the car has turned around 180 degrees, with the trunk nearest the ocean.

At one point, the part in Eddie Albert's hair changes from one side to the other and back again.

At the concession stand, McQ shows Rosey "five bills" in the newspaper then folds the paper closed. Cut to a different angle and the paper is slightly open and the bills are visible. Cut back to the first angle and the paper is closed again.

After McQ shows Myra the balloons of cocaine in his handkerchief and gets up from the chair, the balloons roll off the cloth and onto the floor. When he is rebuffed by Myra and returns to the chair, the cocaine is back on the handkerchief and not on the floor.

When McQ is trapped in the alley by the semis, the car is in the middle of the alley. When the police arrive, one of the semis escapes by driving around the wrecked car, which is now on the side of the alley. When the police officer goes to check the car, it is back in the middle of the alley.

When Myra is murdered, the hitman uses a revolver with a suppressor. A suppressor is effective only when all the gases expelled from the cartridge are channeled through it. Semi-automatics and automatics do this by design because the chamber holding the cartridge is continuous with the barrel. Revolvers, however, have a small gap between the cylinder and the forcing cone of the barrel (the cylinder gap) as a necessity of their design (because the cylinder has to turn). Some gas expelled from the fired round escapes at this point, and this gas discharge is enough to render the suppressor useless. (A possible exception to this would be a gas-seal revolver, but the hitman is clearly using a traditional revolver that shows a flash of gas escaping the cylinder gap with his first pull of the trigger.)

When McQ (John Wayne) breaks into warehouse and isolates the alarm, he clips the bypass cable to the wrong side of the circuit (door).

When McQ is looking into his smashed car in the police impound lot, he retrieves his bag with the Mac10 machine pistol; there is no way that would be possible as the police would have searched the car and found the gun before it was put in the lot.

McQ uses an Ingram MAC-10 9mm machine pistol, which fires approximately 20 rounds per second. No empty cartridges are ejected from the gun when firing the MAC-10 in the car on the beach. Emptying a full 30-round magazine would have sprayed casings all over the car.

In the beach chase, McQ veers right behind a big rock. When he comes out, the stunt driver is clearly seen, and it is not John Wayne.

Several times during the final beach chase, McQ looks into the rear view mirror to track his pursuers, but many times the mirror isn't there, and he's just looking at the roof of the car. The mirror appears and disappears depending on which camera view is being shown.

Confiscated drugs are put in a van to be taken to a plant to be destroyed, and McQ follows the van. Suddenly the van slams its brakes and screeches, then lets up, only to do it again almost immediately as a blue car pulls out in front of it. The funny thing is that the blue car had NOT pulled out in front of the van when the van slammed on its brakes the first time. It was after the van slammed on its brakes the first time that the blue car pulled out in front of the van, causing the van to slam on its brakes the second time. Clearly the van driver realized he was about to pass the blue car before the blue car was ready to pull out. Clearly the first time the driver of the van slammed on his brakes was to give the driver of the blue car the time he needed to pull out in front of him. Otherwise there was no reason for the driver of the van to have slammed on his brakes first time (or two times in such close succession).

As was common with filmmakers of the 1960s and 1970s, the music supposedly enjoyed by young adults was a decade behind the times. While the band at the club was playing mid-1960s fuzz-toned acid rock, the most popular rock bands of the day were such giants as ZZ Top, Queen, Aerosmith, and AC/DC.

Beyond this, the club is not a rock venue but an R&B club, where they would rarely have a live band, but a DJ playing tunes by the most popular R&B artists of the day, including The Commodores, Parliament-Funkadelic, Roberta Flack, Gladys Knight & The Pips, James Brown, and Stevie Wonder.

None of McQ's daughter Ginger's spoken dialogue matches what her lips are doing. Another actress overdubbed her entire dialog.

After McQ finishes his visit with his ex-wife Elaine, her husband Walter, and his daughter Ginger, he turns around and begins to walk away. He doesn't stay on the sidewalk but cuts across the grass. Special Effect walking sounds are edited in here of someone walking on a hard surface (such as cement), which would not be made by someone walking on grass.

Near the end of the film, when two cars full of bad guys show up after the shootout next to the train bridge, McQ and Lois jump into their car and speed off onto the beach. When the tires start to spin on the soft, wet sand, they squeal as if the car was on pavement.

When McQ receives his first phone call while on his boat, which wakes him up, and while reaching for the phone, the hand receiver rattles before McQ touches it for the first time, and then again when he does actually touch it.

At around the 1h 35-minute mark, McQ gets out of the police car he stole from the police lot and leaves it to roll down the hill and crash. When the camera angle is inside the vehicle, black gloves can barely be seen on the steering wheel. When the camera angle switches to outside the car, the silhouette of the stunt driver can be made out occupying the driver's seat, dressed in black. The director uses shadows and camera angles to obscure it as much as possible, but the stunt driver is still vaguely visible.

When McQ goes to visit Pinky (David Huddleston) for the first time in Pinky's office and they get up to leave, the microphone wire can be seen taped under Pinky's dress shirt.

In the last scene on the beach, a movie light with an amber gel can be seen reflected in McQ's car.

When Stan Boyle (William Bryant) parks the car he used to kill the cops from in the used car lot, he reaches out the window to open the car door while wearing gloves. Then takes the gloves off, puts them in the leather pouch with the gun, and puts his hand on the steering wheel to steady himself while getting out of the car. Since he was wearing gloves, it would not matter whether he used the inside door handle, so there was no reason to reach through the window to use the outside handle. Also, since he had taken the gloves off, he should not have touched the steering wheel with his hand and fingers. A veteran cop would have known these things, and more than likely would have kept the gloves on until after he passed the car lot's chain link fence, which he also touches with his bare hand/fingertips on the way out.

When McQ leaves the state building after the drug heist to follow the laundry truck, he runs to his Trans Am, opens the door, and is seen getting in head first before the cut away. As John Wayne was 6'4" tall, it would have been impossible for him to get into a Trans Am that way; he would have to go right leg first, then slide into the seat, tilt his body to the left as he does it, and twist his neck out of the way until his butt hit, and slide across the seat, which is the way he is seen to do it when he comes out of Pinky's office into the alley.

At 0:52, McQ is following the van with the drugs. They exit the expressway and come to a stop sign. The van stops and turns left. A pickup truck is coming down the street and comes to a full stop to allow McQ to exit and continue to follow the van. There was no stop sign for the cross traffic, and there was no traffic that would force the pickup to stop. There was no reason for the truck to stop, unless the director ordered it to keep McQ from being separated from the van.