Blooper

When Mitch is taken to a secret location to meet with the extortionists, he sits in a wooden chair against a "wall". He sees his mistress shot five times. After the bad guys leave, he jumps up when he realizes he is in the chair she was murdered in. But, when he first walks in, there is no blood on the chair or wall behind him.

When Doreen strips for Harry she gets down to just panties, then in later reverse angle shots she her garter reappears.

Near the beginning of the film as Harry enters Cini's apartment we hear a gun being cocked and then see a .45 pistol being pointed at Harry's head. You can see the hammer is not in the cocked position.

In the final scene when Alan starts the E-type Jaguar he does it by turning the key, yet that car (as to all pre-1968 XKEs) starts with a starter button on the dashboard, as was demonstrated when it first appears in Harry Mitchell's garage.

The "exploding" Jaguar is slightly different than the one used throughout the film. It has a dent between the door and bonnet, lacks the passenger-side rear-view mirror, and the hard top is missing the glass rear window. Given the value of the car it is forgivable that the "real" one was not blown up.

At 15:55, lighting and shadows reveal an obvious spotlight in use as camera moves behind the men in hard hats.

Around 1h32m, Mitch's lawyer suggests letting Leo testify. Mitch responds by listing the digits of Leo's number as 657-1333, which the lawyer starts dialing. We immediately cut to a close-up of Leo's phone ringing, with a typed label reading 213 555-4953 in the center of its dial.

When Raimy drives to Harry's factory to meet him, it's supposed to be 12:45 at night, but the sun is clearly either rising or setting in the establishing shot as he drives up.

When John Glover was back to the camera waiting Roy Scheider shows the money to exchange Ann Magret he back away to much far as to bump in the camera, unfortunately the sequence wasn't redone even largely noticed.

When Harry Mitchell walks into the adult theater, you not only see the reflection of the camera man, but you also see the reflection of the boom mic in the open glass doors for a moment.

When John Glover is seen manhandling Ann-Margret at the bridge location (and just before he puts her in the trunk of a car) you can see the shadow of the camera on them at one point during their struggle.

When Barbara drives to work at the beginning of the film, the exterior sequence shows her driving through Century City, to the west of their house in Hancock Park, but once she's in her office, the views from the windows show the building is in Downtown Los Angeles, to the east of Hancock Park and 30 minutes away from Century City.

After Bobby shoots up Raimy's place, he holsters his pistol with the hammer cocked. An experienced gunman would never do this.