Owen Gleiberman Chief Film Critic In body-swap comedies, the acting is its own kind of brazen put-on fun. Adult actors get to channel their inner innocent kid; young actors get to channel their “serious” adult. And that’s why, ever since the original “Freaky Friday” (1976) brought this genre into being, it’s been marked by instances of true Hollywood artistry, like Tom Hanks’ classic performance in “Big” (though that wasn’t technically a swap comedy) or the lyrically funny bedlam that Jennifer Garner brought off in “13 Going on 30,” one of the best movies of its year.