Precious, predictable comedy has overworked father Judge Reinhold and pre-teen son Fred Savage switching personalities after getting hold of one of those movie-formula ancient mystical artifacts. Hoary premise plays like just another "Freaky Friday" retread, however it gives Reinhold the opportunity to really cut loose, and he has fun (although his overacting is shameless). Savage, then-star of TV's "The Wonder Years", fares even better, doing his wiser-than-his-age shtick with letter-perfect ease (he's a natural). There are some laughs, although the whole thing bottoms out in the final stretch with a ridiculous car-chase. Smart viewers will have bailed out by then. *1/2 from ****