Revealing mistake: In the scene where Cully injects Sonny in his back, you can see that just just after he pushes the plunger, the spring mechanism moves on the inside of the syringe. He is not actually injecting Sonny, but the needle retracts on a spring loaded mechanism into the syringe. (00:14:40)
Hooper (1978)
1 revealing mistake
Directed by: Hal Needham
Starring: Burt Reynolds, Sally Field, Brian Keith, Jan-Michael Vincent
Continuity mistake: There is one scene in the final earthquake as Ski and Sonny are driving around the city that's being destroyed - the Trans Am gets hit from the right side, hard enough to throw the car into a small skid, but seconds later there is no damage to the car, and nothing like that was discussed during the planning of the stunt. One has to wonder if that hit was unintentional and not scripted.
Jocko Doyle: You oughta drink more. Nothing hurts when you're numb.
Trivia: When everyone's back at Sonny's ranch watching his old stunt films, the footage with him getting thrown from a canoe in a river was from his movie "Deliverance".