Americans like cartoons of transformation, fantasies of sudden empowerment. Popeye eats spinach. Clark Kent enters the phone booth. The 97-lb. weakling sends away for the Charles Atlas course. Shazam! The creature that a moment ago looked mortal and ordinary and vulnerable becomes a master of the universe. He can fly. Conquer evil. Get revenge. He is born again, this time as a kind of god.
Sylvester Stallone has a shrewd mythmaker's instinct for that kind of metamorphosis. Stallone's formative influence was the Hercules movies of Steve Reeves, whose physique he energetically and wistfully labored to replicate. Stallone eventually took his splendidly...