Efron fares well in time-bending flick

Implausible but altogether pleasant. Slapstick but also humane.

It seems the negatives balance out the positives with the lightweight comedy-fantasy “17 Again.” Add the charisma of today’s teen idol of the moment, Zac Efron, and the balance tips in favor of this movie.

As a vehicle for Efron, who won a legion of female teeny­bopper fans via the “High School Musical” trilogy, it is not only appropriate, it is somewhat ingenious. Efron faces the difficult task of finding a wider audience while keeping his sweet, young fan base intact. By playing a teenager who is actually his 37-year-old father, Efron gets to look untouched by age while, at the same time, playing some adult trauma. He can be Dorian Gray with no need to hide in the attic.

One of the many implausibilities is that Efron would, or could, turn into someone who looks like Matthew Perry of the “Friends” TV series, even in 20 years. Perry has the thankless job of playing the bad side of all things. He, back when he looked like Zac, was on the brink of a college basketball scholarship when he panicked because, just at tip-off, his girlfriend informed him she was pregnant. He runs off the court. Twenty years later, the couple’s two children are distant brats who have been made that way because Dad neglected them. He gets overlooked for an advancement at his pharmaceutical job. Mom (she of the long-ago pregnancy) is divorcing him, apparently because he keeps harping on his great sacrifice of the past.

But not all is lost. With a plunge off a bridge, apparently engineered by the school janitor, he looks like Zac Efron and can go on one of those “If only I knew then what I know now” trips.

There is a hint of “Big” in reverse (but with none of the real wit) and of the life-affirming qualities of “It’s a Wonderful Life” (but with no real development). The janitor, one supposes, is meant to be a subplot angel, or something, like Clarence in “It’s a Wonderful Life.” The occasional knockabout slapstick bits keep you from snuggling up to this movie the way you do “Life” at Christmastime.

There are, however, some nice moments for Efron, who comes across in every case as someone who may well outlive teen stardom. He has a funny scene in which he lectures the girls in his class about abstinence (on behalf of his 37 side).

He gets to humiliate the bully who is dating his daughter and to teach his shy son to stand up for himself.

His best scene comes in a courtroom, where he lets Mom, his wife, know that he really did care all that time. It could have been too cornball, but he pulls it off.

Leslie Mann of “Knocked Up” shows no particular flair as the wife-mother who is mysteriously attracted to the teenager who looks like her husband back then. This relationship should have been funny rather than quirky. (The setup is borrowed from “Back to the Future.”)

If you had a daughter, you’d be glad for her to date Zac.

This movie is also that safe.

Mal Vincent, (757) 446-2347,

mal.vincent@pilotonline.com