Revealing mistake: During the whole movie any time someone is driving, the driver turns either way too much or not enough for the turn they are on. Even when they are driving straight, they turn the wheel as if they are going back and forth on the road in both lanes.
Continuity mistake: Spencer Tracy says they will go to the crossroads and turn south (a right-handed turn according to the wall map he's looking at). When they get to the crossroads, they all turn left which would be north.
