Continuity mistake: Emily Sloane's left ring finger was shipped to Arvin Sloane in one episode in Season 2, when they are reunited in the Philippines, the left ring finger is bandaged and missing. Later, in the episode when she is shot, when she tells Arvin the CIA is listening, the left ring finger is there.
Continuity mistake: Season premiere, 'Authorized Personnel Only', part 1: When Sydney and the other agent are in the bathroom at the club, Sydney begins to smear black dirt on the agent's tee shirt for his punk transformation. The first smears that she applied differ when he exits the bathroom.
Continuity mistake: When Sydney is tortured, she loses some teeth and a stream of blood flows out the right side of her mouth. When she returns to SD-6 and speaks with the director, the blood is gone (fair enough). Outside on the street in the following shot, the blood has returned, but there's no reason to believe that she is still bleeding. (00:58:40)
Continuity mistake: When Sloane is talking to Sydney towards the end, he slides some documents towards her. After that shot, when the shot's of Syd we can see that Sloane's holding his hands near his face, but in front shots of Sloane they're down by the desk. (00:37:30)
Continuity mistake: When Roger Moore is showing Sloane the bank accounts, he says "5 deposits in excess of $45 million...", but the shot just before that shows deposits of (in thousands), $9,362, $7,215, $9,010, $8,300, and $9,250. That makes $43,137,000, which isn't in excess of $45 million. (00:20:10)
Continuity mistake: In the parking garage, after Sydney knocks the machine pistol out of the hit man's hands, it lands with the barrel pointing away from The Two of them and remains in that position during their entire fight. When Sydney grabs it off the ground, the barrel is pointing toward them. (00:43:30 - 00:44:10)
Continuity mistake: In this episode Nadia Santos tries to find out who's the baby that her mother Irina Derevko is holding on a picture. She first shows it to Jack Bristow and later to Arvin Sloane. Later Jack asks to see to picture again and tells Nadia it's Irina's niece. At the several moments the picture is visible the picture is flipped, showing the baby on the left arm or right arm of Irina. (00:29:55 - 00:36:35)
Continuity mistake: In 'The Abduction', when Sydney shuts down the traffic lights Sark's car is in the middle of the gridlock. When Sydney is fleeing with the stolen briefcase seconds later Sark pulls up beside her to save her, but how did he get out of the huge gridlock?
Continuity mistake: When the new head of SD-6 invites the security agent to play back what Sloane wrote, the screen is already displaying the letter. We only see the entirety of this letter later, once the "playback" has been completed. It can't be that the boss has done it once already, as he's surprised to see the final text.
Continuity mistake: Between the pilot episode and the second episode of Season 1, the swing of the blast door on the secret base reverses. In the pilot, the hinge is on the right and it opens from the left. In episode two, the door opens from the right with the hinge on the left. (00:12:05)