After the creepy, thin man shoots at the angels during his escape in the Chinatown alley, a squib wire (which makes a bullet impact) can be seen next to Alex's head.
When Natalie kicks the board that Vivian throws at her, you can see the strings used to pull the wood apart.
The picture of the "tall thin man" coming out of the fax in the car is different from the one the angels look at a few seconds later.
When Alex is making the roast dinner, she places a couple of carrot pieces on the roast. In the next shot, there are no carrot pieces on the roast.
The muffin in the door changes positions.
When Dylan jumps out of the airplane, her jacket is unzipped, but when she lands on the beach, her jacket is zipped up.
At the exotic dance club, Director #1 clearly is holding his beer bottle by his fingertips, and not touching it with his pinky; Dylan's scanning device shows a full handprint including his palm. Director #1 holds the beer bottle with his right hand; Dylan uses the fingerprint "glove" on her left hand. A sophisticated gel scanner would be able to distinguish the difference in the sequence and location of the fingerprints; a left handed print of the right-hand fingerprints would not work.
Dylan makes the fingerprint "glove" for her right hand, but later she is seen wearing it on her left hand.
A retinal scan is a scan of the inside of the eye, not the visible external part. At Director #2's house, the device clearly scans the Director's iris. The contacts that are made from this would only disguise Natalie's iris, not her retina. A sophisticated retinal scanner would distinguish the location of the retinal image as well as the image itself; an external contact would not work.
When Nox shoots at Dylan and she goes through the window, the shards of the glass not only change shape when she's hanging from the sheet, but the glass itself changes form entirely. When she's sent through the window, it's made of tempered glass (shatters into pebble like pieces) yet when the sheet was hanging from the spike of glass, it was a non-tempered kind.
When the Angels are in Bosley's office and Charlie is introducing Eric Knox, the video of Eric Knox on the flat screen is reversed. This becomes obvious after noting that "Boston" is reversed on his sweatshirt.
When the angels are all talking to Vivian Wood and Eric Knox in the "umbrella" lunch area, Vivian's sunglasses show an obvious white background, when the real background behind the Angels is clouded skies and more buildings/umbrellas.
While the Nokia Communicator cell phone rings, there is the name "CHARLIE" displayed on the LCD screen. But, instead of giving the owner an option to accept or reject the call, the display reads "Detail" and "Exit". This proves no one is calling - someone is just browsing the phone's memory.
The first scene in which Natalie talks on her cell phone, it's a Nokia 8260 with red faceplate. Later on she talks on her cell phone but it's a Nokia 8860 with the shiny silver slide.
When Alex first sees the thin man, Alex and Dylan are both wearing shoulderless and sleeveless dresses. As they chase him down the stairs ripping off items of clothing to prepare to fight, Alex ends up in a bodysuit complete with sleeves and shoulders.
Just before Knox shoots Dylan out of the window, he eats a strawberry, and spits the pips at Dylan. A pip appears and disappears on Dylan's chin, just before she falls.
When Alex is fighting the thin man in the bell tower, he cuts the rope and the bell falls, yet in all subsequent scenes in the tower, the bell is visible.
The video footage of Knox's kidnapping is black and white, yet the "enhanced" photo of Creepy Thin Man taken from the footage comes out in color.
In the final fight, Alex wears high heels, then flat shoes.
The right door of Knox's helicopter opens and closes at random intervals.
When the Angels are hanging from the bottom of Knox's helicopter, long shots show them all in a sitting position. The close shots show them in different positions.
In the helicopter scene, the Angels are wearing high-heeled black boots in the close-up shots but the long-shots show flat-heeled black sneakers worn, presumably, by the stunt doubles.
After Jason's trailer gets riddled with bullets he and Alex are standing outside with the western backdrop in the background. Most of the bullet holes have the sharp edges coming outwards, but the shooters were shooting toward the backdrop, so that side of the trailer should have had the holes going inward.
In the opening sequence on the boat, the terrorist's black vest appears and disappears between shots.
When the angels arrive at Bosley's office, it explodes, with pieces shattering the Ferrari front window. When leaving the scene, they drive away with a perfectly intact windshield.
Looking directly at the revolver when Dylan is shot at, you can clearly see truncated cone lead bullets. The following slow motion view is of a full metal jacket bullet.
The bird is not a pygmy nuthatch, but even if it were, it is found all over southern California, not just in Carmel.
During the race car scene, the Angels are at the California Speedway in Fontana, California. A few seconds later, the chase leads them to San Pedro, California, 70 miles away, where the Vincent Thomas Bridge is visible.
At the party, Corwin hands Bosley a tray of blowfish. The tray is uncovered, but in the very next shot, we see Bosley removing a piece of Saran wrap from the tray.
The satellite image of Charlie's cabin is obviously not from a satellite. Satellites would provide a "top view" of the cabin, not a perfectly horizontal one.
When the Angels first chase the Thin Man, the camera is reflected in the shiny metal door of the elevator.
When Natalie and Vivian are fighting, you can see the small of Vivian's back a couple of times, indicating that she is wearing a two-piece suit (trousers and a top). However, after she rips off her jacket after she and Natalie roll down the stairs, she is wearing a one-piece garment (catsuit).
When Knox shoots at Dylan the bullet is on her left side. In the slow motion retake it's on the right side.
Natalie's cell phone disappears and reappears in her battle with Vivian.
The camera is reflected in Natalie's backpack on the beach.
At the end scene on the beach, there is a shot of Charlie walking off to the left along the beach. The setting sun is reflected in the sea behind him. In the next shot (looking squarely out to sea, with Bosley and the angels in the foreground) the sun is high and to the right of the camera.
When Alex goes to jump on Corwin to massage him, she clearly jumps to the left of him, but from our point of view she jumps behind him.
Near the beginning of the film, one of the Angels jumps into the car on the pier and it is at an angle facing wooden pylons. When she hits the accelerator the car takes off in a straight line down the pier.
Before Natalie breaks into the RedStar vault, she is wearing a head covering and a breathing apparatus. When she (stunt double) is tumbling through the vault and when she makes the connection to the RedStar computer, she is no longer wearing the head covering or the breathing apparatus.
When Natalie is dancing on the Soul Train stage, all of the audience stop and stare. But when we see shots of Pete, we can see them dancing, when they should be standing still.
After Bosley's office blows up, The Angels drive off in Natalie's car (a red Ferrari) but when Dylan says, "Head to the marina," the car that they are driving is a black Ferrari.
When Dylan throws the muffin at Natalie in the office, Natalie is heard to say "Ow!" But her lips don't move.
Source: imdb.com