Sex Tape

“Sex Tape” is like an episode of a filthy sitcom that was stretched from 22 minutes to 94 even though they barely had 22 minutes’ worth of story. Starring a slimmed-down Jason Segel and a very game Cameron Diaz, it centers on a workable premise: what if you filmed yourself doin’ it and then accidentally uploaded the video to the Internet? What would you do? But screenwriter Kate Angelo (“The Back-Up Plan”), with assists by Segel and his regular collaborator Nicholas Stoller, doesn’t seem to have pondered the question any further than that. The answer is that everybody runs around screaming and flailing their arms (figuratively, but also sometimes literally), coming up with panicky, last-second lies, and ranting about the Cloud the way people 30 years ago ranted about arcade games (and with a similar level of understanding of how they work).

Segel and Diaz play Jay and Annie, a married-with-kids couple whose once vigorous sex life has diminished in recent years. They make a sex tape to spice things up (as one does), but wouldn’t you know it, Jay inadvertently puts it in the Cloud. Now everyone with access to Jay’s Cloud account — which for some reason is everyone they know, because for some reason Jay’s job at a radio station means he always has lots of extra iPads that he gives away as presents, and for some reason those iPads’ new owners never update the preferences — has access to the footage. That includes Hank (Rob Lowe), the corporate bigwig whose squeaky-clean, family-oriented toy company is considering buying Annie’s mommy blog! What is HE gonna think?? ZOING!

There are scattered laughs along the way, thanks mainly to supporting characters played by Rob Corddry, Ellie Kemper, Kumail Nanjiani, and a few others (including an amusing cameo near the end from someone playing a porn guru). Most of these laughs are from individual lines of dialogue, though, not the situations. (“You can see their different personalities already,” Nanjiani says of his baby twins. “This one likes watermelon, this one’s kind of an a**hole.”) Segel and Diaz, who worked together in the similarly lackluster “Bad Teacher” — which, like this, was directed by Jake Kasdan — have a buoyant chemistry and an ego-free willingness to do anything that helps some. But they can’t overcome the weakness of the meandering, undercooked screenplay, which builds itself around an overlong sequence at Hank’s mansion and then wanders into a dumb, implausible blackmail subplot before going completely off the rails with a desperate attempt to retrieve the video from a Internet server’s offices. I find it hard to believe any of these writers couldn’t come up with funnier ways to exploit this premise.

C (1 hr., 34 min.; R, abundant harsh profanity, some naked butts and side boobs, graphic sexuality played for laughs.)