Channing Tatum is the only draw in ‘Dear John’

For guys on date night and film critics, they are the seven most feared words in a movie ad: “Based on a book by Nicholas Sparks.” The best-selling romance novelist, with delusions of literary grandeur, has churned out the trendy trash behind some of the cheesiest tearjerkers in recent years. In the overrated “The Notebook” and even worse “Message in a Bottle,” “A Walk to Remember,” and “Nights in Rodanthe,” Hollywood’s gorgeous minions have crashed in waves of overacting and overplotting on Sparks’ favored Carolina shores. In today’s “Dear John,” two more very pretty people sink under the weight of the author’s melodramatic manipulations (by way of a Jamie Lindon screenplay adaptation) and their own on-screen insufficiencies.

It’s tempting to recommend this weak chick flick to certain chicks anyway: There are probably worse ways to spend 105 minutes than beholding the luscious lips and freckled trapezoids of “G.I. Joe” ‘s hot Channing Tatum (who has a devoted young female fan base). Behold him. For much of the film’s first act, he romps shirtless on the beach as inscrutable Surfer Boy/Green Beret-on-leave John Tyree.

Before he goes back overseas, John has two weeks to woo cute co-ed Savannah Curtis (“Mama Mia” ‘s Amanda Seyfried). His hitch is supposedly done in a few months so they can be together forever.

But then, with precisely timed inconvenience, obstacles arise to keep on keeping the saintly lovers apart. We can already guess, since the courtship begins in the spring of 2001, that the immense tragedy of 9/11 will be used for superficial narrative purposes here. But then this commercial venture also diminishes the very real, painful issues of autism, terminal lymphoma and the sacrifices of our military families as ways to toy with the affections of the two main characters.

Supporting players Richard Jenkins as John’s challenged father and Henry Thomas as Savannah’s vulnerable ally, meanwhile, are left helpless to play their victim roles. And even against some beautiful production values, especially the cinematography, Tatum and Seyfried both lack the oomph and expressiveness to carry a feature film well.

Surprisingly, quality director Lasse Hallstrom (“The Cider House Rules,” “What’s Eating Gilbert Grape”) chose to work with this material and employ these young stars. Maybe, since the filmmaker hasn’t had a success since 2000’s “Chocolat,” he needed a job. But, Dear Lasse, I’m sure you know that “Dear John” is beneath you.