Ashton Kutcher is way buff.

Katherine Heigl is beautiful, busty, and slim.

And the south of France, where their new flick, the eminently missable Killers, is set, is gorgeous.

Hmm - so what else is there to say about this most mismatched pair's ill-conceived, boring, cliche-driven, humor-challenged romantic action comedy?

Did we say the scenery is nice?

Directed by Robert Luketic, the genius who gave us the insipid Heigl romance The Ugly Truth (2009), Killers is about a (really, really buff) CIA assassin (Kutcher) who falls for a geeky, clumsy computer nerd who happens to look - well, like Heigl.

Heigl is Jen, a cautious, un-spontaneous all-American lass recently dumped by her boyfriend. As the film begins, she's suffering through a family vacation in Nice with her insufferable parents (Tom Selleck and Catherine O'Hara). She's so very sad - she was supposed to go there with her cad of an ex.

Within 10 minutes of checking in to her hotel, Jen has met and fallen madly in love with a topless Spencer in the elevator. The sparks fly! The passion swells! That ultimate abyss, love, opens up!

If only! Sadly, Heigl and Kutcher have about as much chemistry as um, Heigl has had with every one of her previous costars. As beautiful and talented as she is, Heigl has a singularly unsexy, dispassionate onscreen presence.

At a certain point, it actually becomes embarrassing to watch Heigl and Kutcher play at being in love.

But the screenplay says they are. So, they marry and move to a beautiful California suburb, where Kutcher quits killing people and starts a construction company. It's his dream life; as an orphan and a trained killer always on the road, he has yearned to settle down.

But it's not to be. Kutcher's CIA boss refuses to let him retire, and before long, the Buff One is hunted by an army of hit men and women - Katheryn Winnick looks really hot when she goes all kung fu on him.

Nothing fits in Killers. Selleck, an otherwise charismatic player, looks stiff, out of place. O'Hara is forgettable as a boozed-up lush. Watch this one on cable, if you must.

Killers * (out of four stars)

Directed by Robert Luketic. With Ashton Kutcher, Katherine Heigl, Tom Selleck, Catherine O'Hara. Distributed by Lionsgate.

Running time: 1 hour, 39 mins.

Parent's guide: PG-13 (some adult language, mild violence, extreme insipidity)

Playing at: area theatersEndText

Contact staff writer Tirdad Derakhshani at 215-854-2736 or tirdad@phillynews.com.