21st May 2006
One of Them - S2-E14
Revealing mistake: When Sayid and Locke are talking to Henry Gale in the hatch, just as Jack comes in and finds them, the front part of the arrow supposedly piercing Gale's shoulder is at a different angle to the back part. This is visible in a number of shots.
24th Mar 2006
Exodus (2) - S1-E24
Factual error: Hurley arrives at the departure gate and calls to the woman to wait and let him board. As he goes through the gate, a sign with the word 'authorized' is visible to the left. This scene supposedly takes place in an Australian airport, but this is the American spelling - in Australia, the word is spelled 'authorised'.