Continuity mistake: During the cemetery scene where they visit the son's grave, you see a wide shot of them walking between the stones. There are leaves on the trees and neatly trimmed grass. When we see a close up of the stone and the plaque in the ground, a hand reaches down to brush the leaves off so they can read it, and there are dead leaves all around - but there were no leaves on the ground in the wide shot.
![Face/Off mistake picture](/images/screenshots/139000-139999/139074_sm.jpg)
Continuity mistake: When Jaime is screaming, Castor Troy (as Sean Archer) walks out to the front yard and the back tires/end of Karl's car is on the sidewalk, but when Karl is dragged out, the car is farther up the driveway. (01:24:50)
![Face/Off mistake picture](/images/screenshots/139000-139999/139208_sm.jpg)
Continuity mistake: During the prison breakout, when Dubov falls over the railing after being shot, in the first overhead shot he falls backwards, but next shot he falls forward (chest down). (01:11:40)
Continuity mistake: When Troy (as Travolta) is about to defuse the bomb, watch the timer, it goes down too slowly for the time elapsed. It shows 1:14 and 28 seconds later it only shows 1:04, not 0:46 as it should. (00:58:45)
![Face/Off mistake picture](/images/screenshots/86000-86999/86497_sm.jpg)
Continuity mistake: When Castor arrives at the airport, behind him there is a parked car in front of the building which on it reads "Welcome to Southern California International Airport", that disappears and reappears.
![Face/Off mistake picture](/images/screenshots/139000-139999/139314_sm.jpg)
Continuity mistake: After Sean types "case closed" on Castor's file, Dr. Miller walks into Sean's office and holds out Pollux's Zip Disk for Sean to take. In the next close-up, the Zip Disk has flipped over and faces the opposite way.
![Face/Off mistake picture](/images/screenshots/139000-139999/139202_sm.jpg)
Continuity mistake: When Archer gets into the chopper and takes off, the next shot is of the chopper flying towards the camera and it is not Archer who is flying it - the chopper pilot wears head gear and a mic. (00:11:40)
![Face/Off mistake picture](/images/screenshots/139000-139999/139334_sm.jpg)
Continuity mistake: After the incident with Karl, when Castor (as Sean Archer) and Jamie are in the living room, he opens the cigarette case and offers her one. The way he holds the case noticeably differs between shots.
Continuity mistake: When Castor (as Sean Archer) grabs the speargun shaft before it can unload, he takes a piece of glass and begins to cut his face. The broken glass has a small circular piece missing from the edge, but from a different camera angle that small piece is more intact than the previous shot. (02:09:15)
![Face/Off mistake picture](/images/screenshots/139000-139999/139207_sm.jpg)
Continuity mistake: When Castor Troy (as Sean Archer) says, "Every time you'll look in the mirror, you'll see my face," he proceeds to cut his face. The first cut he makes is straight down the side of his right cheek (viewer's left) and later that cut is curved and closer to his nose. This may appear to be a mistake at first glance; however, Castor's facial expression is different in the two images. When he made the cut, the cheeks were pulled away from the nose; in the second photo, the muscles are relaxed, moving the cut closer to the nose. (02:09:15)
Continuity mistake: At the hangar, when Castor Troy is blown backwards in the turbo tunnel he hits the wire gate, and the metal bar, about 3-4 ft long, breaks off and begins to fall with him. Next shot, he lands on the floor, but the long bar does not. It just disappears. (00:17:45)
Continuity mistake: After the surgery, when Sean (as Castor Troy) breaks the center mirror of the tri-fold mirror, what remains are the two side mirrors and white backing within the center frame. When Tito grabs him as he starts cursing, in these close-ups the reflections seen are as if all three sides are still intact. (00:37:15)
![Face/Off mistake picture](/images/screenshots/139000-139999/139103_sm.jpg)
Continuity mistake: During the runway pursuit, there is a shot from behind Castor Troy as he fires on Sean's chopper, and there are four bullet holes on the windshield. In Sean's close-up the four bullet holes change position.
Continuity mistake: When Cage is rolling down the runway he appears to be controlling the direction of the aircraft by turning the yoke. An aircraft is controlled on the ground via rudder (vertical stabiliser) controlled by the feet of the pilot, and nosewheel steering, also controlled by the feet (rudder pedals) of the pilot (sometimes also with a steering wheel on the side of the cockpit). Moving the yoke simply alters the position of the ailerons, which will not steer the aircraft on the ground.
![Face/Off mistake picture](/images/screenshots/238000-238999/238719_sm.jpg)
Continuity mistake: While Sean tries to prevent the jet from taking off, in the exterior long shots of the aircraft there are windshield wipers over two of the cockpit's windows, but in the exterior closeups such as when Castor brings Winters into the cockpit the wipers are gone. (00:06:35 - 00:10:20)
![Face/Off mistake picture](/images/screenshots/160000-160999/160720_sm.jpg)
Continuity mistake: On the speedboat at the end of the movie when Archer and Troy fly through the air, you can see foam on their clothes even though in the next scene their clothes are dry. (02:02:25)
![Face/Off mistake picture](/images/screenshots/66000-66999/66817_sm.jpg)
Continuity mistake: In the scene where Cage and Travolta are fighting on the dock, Cage stabs Travolta with the speargun (before he fires it). If you look at the spear after Travolta is stabbed, there is blood on it. Then in the next shot, the spear is suddenly clean.
Continuity mistake: At their home, when Sean tells Eve that he has one last assignment we see his scar. At the Walsh Institute, before the surgery, there is another close-up of the scar, but it differs from the previous shot. (00:30:20 - 00:33:05)
Continuity mistake: When John Travolta's daughter slams her bedroom door in his face, from one shot it nearly closes, but in another shot he blocks it when it's still got a long way to go. (00:54:35)
Continuity mistake: At the office, when Sean is given the bottle of wine for a job well done, the way the bottle is held, first by the assistant and then by Sean, differs between shots. (00:20:40)
Chosen answer: Although they were on the same side, Troy is currently posing as Archer, which means he would have to do everything that the FBI would expect Archer to be doing. The whole point of the raid was to take out Archer, as well as Troy's gang. He would have rather risked killing part of his own gang than risk exposing his identity to anyone else.
Casual Person
That doesn't really make sense. In the scene, he goes out of his way to shoot him and smiles while doing so, carefully and slowly. Was not a collateral damage situation. The question is why he deliberately goes out of his way to kill him.