Continuity mistake: Morgan and Sophie walk towards the fifth interior arch ring in the tunnel, but when the man (Alec) points a gun behind Morgan's head, Morgan is near the third arch ring. Although they move back and forth during their fight in the tunnel, the number of arch rings reaches 10, but they are back to the 3rd arch when the camera shifts. (00:24:13 - 00:24:51)
Continuity mistake: Morgan and Sophie take far too many steps to get into the tunnel, then take many more, which take them past the man on the left, but the man is still ahead of them. After they take more steps and are past him, they are back at the tunnel entrance. (00:23:18 - 00:23:50)