Sex Tape review: these nude selfies are not worth a look

There have been worse years for the film industry than 2014. Nonetheless, this gormless farrago feels like the manifestation of a vast collective nervous breakdown. The rom- com has been withering into mulch ever since the Chick Flick gene was grafted onto its hitherto robust molecule. Men were consciously repelled. Then women began fleeing the rotting corpse with handkerchiefs pressed over crinkled noses.

Hollywood faced a similar dilemma in the early 1970s and reacted by asking its stars to drop underwear in mildly risqué sex farces. The relentlessly awful Sex Tape feels like an equally misguided attempt to connect with elusive, slippery sprigs of the Zeitgeist.

As you will have almost certainly guessed, the picture concerns a couple whose personal sex tape – recorded to energise a flagging marriage – gets set loose on the digital cloud. What we end up with is the very quintessence of a film that has no natural audience.

It’s too sexually explicit to play as a cosy date movie. It’s not explicit enough to work as an erotic piece. Technophobes will not identify with the endless references to file-sharing protocols. The technically literate will find the heroes’ bafflement more irritating than amusing.

We begin with Annie (Cameron Diaz) telling her mummy-focused blog (and us) about the progress of her relationship with Jay (Jason Segel). In the first few weeks of their romance, they have sex in all kinds of unlikely places and at all hours of the day and night.

Eventually Annie becomes pregnant and the couple inform her parents that they intend to get married. "But you're very, very young," her reluctant mother says. Aside from anything else, this is most unkind to the film critic, who now must decide whether it's polite to mention that Ms Diaz was born during Richard Nixon's first term.

At any rate, Annie and her “very, very young” beau – played by an actor in his mid-30s – then discover the perils of matrimony. It’s all relative, of course. Given the nauseating luxury of their lives, Annie and Jay can probably cope well enough with a diminution of libido. She writes her blog on large white sofas. Jay does something or other in the music industry that pays well enough to allow him to give away “used” iPads like other people donate worn socks.

Sex Tape abounds with such Chekhovian guns over fireplaces (the only mention of that Russian playwright you'll meet in this review). Early on, the couple's son, working on his school project, is urged to make sure to label a film something other than "Video 1". Soon enough, such IT sloppiness allows the titular sex tape to be scattered about the territories.

The picture does break ground in one unlovely area. When the history of product placement comes to be written, Sex Tape will receive a chapter all to itself. For years, Sony films have been unique in their determination to resist the advance of Apple products through the cinematic universe. It is no accident that Spider-Man uses a Sony Vaio laptop and a Sony Xperia phone. Yet Sex Tape is soaked in Apple products. What on earth is going on? Does one wing of Sony not want its goods associated with squalid doings in another of its wing's films?

Much stranger still are the copious references to a real-life pornographic website (which, of course, we won’t name) in the last, panicked act of the movie.

Something properly disturbing is going on here. It seems as if these enterprises have now gained enough respectability to feature in a film starring the man who wrote The Muppets. What a world.