A. B. and C. - S1-E3
Revealing mistake: In the fight at the end of the B scenario, Number 6 has a small problem. His pants split open in the back. Fortunately, they somehow manage to mend themselves again.
Revealing mistake: A chalk outline on the parking garage wall where the actor playing the alien that just got shot and disintegrates is supposed to place his body and limbs for the special effects (the disintegration) is visible. The actor placed his body just outside the chalk outline, and the arms were not in the correct positions.