Continuity mistake: When the bomb under the bus is being defused, it's counting down and beeping once every second. We see the timer at 0:45, then cut to the face of the woman defusing it - counting the beeps when we cut back it should be on 0:45, but it's jumped up to 1:06. Camera pans down to her face, then back to the bomb, and it's now on 0:43, but going by the beeps it should be on 0:36. We cut away again for 5 more beeps, cut back and the bomb's only just ticking onto 0:41.
Continuity mistake: When the hostages try to get some rubble to catch fire, they find that everything is covered in some flame retardant stuff. Yet, in the very first episode one of the very first things they do is to make a small fire to get the fire alarm going.
Continuity mistake: In episode 3 or 4, one of the characters is knocked out and lying on the floor in the Russian sub. He is on the 'left' side of the shot most times he is shown, but occasionally he's on the right.
Episode #3.2 - S3-E2
Continuity mistake: Dalton and the terrorist are fleeing from the building when Locke arrives and hits the terrorist who has backed into the street with his car, thereby saving Dalton. The terrorist flies over the hood and lands behind the car in the street, never going anywhere near the driver's side of the car. Locke reenters his car to a broken driver's side mirror.
Come On, God - S2-E8
Continuity mistake: In the scene when Louis C.K. Turns on the radio, is shows station 90.1. In the next shot of the radio, the same song is on, and it reads 91.1. (00:08:45)
Pumpkinhead - S2-E5
Continuity mistake: One of the pumpkins that the kids bring home is completely different to the ones they took from the pumpkin patch.
Continuity mistake: Jack rushes in at night to save Kate who has been drugged by the evil professor. Jack resuscitates her and calls an ambulance. When the ambulance leaves it is bright daylight.