While showing off, I've shot a Ruger 22 pistol sidewise and upside down. I suppose with enough practice, it could be considered an option, albiet a poor one. The normal upright hold does a better job of helping control recoil because the weight of the shooting hand/arm is directly below the angle of the recoil movement. Not a factor with a 22, but comes into play with 9mm and up. Some pistols don't function well at odd angles although revolvers don't care. The sights are going to be way off(if you use sights) since they're setup for shooting upright and recoil figures into the angle of the barrel at the moment the bullet leaves the muzzle. Even a laser sight will not be aligned properly for the same reason.
IMHO just a Hollywood farce. If you use this method, use a big target and get close.
BTW if you want to get really tricky, use two pistols. One in each hand held horizontally top to top with the sights close together and try to get them to fire and hit at the same time. Not recommended for home use.