Not that they don’t try. There is a desperate energy driving the feud between Kate (Eva Longoria Parker), a wandering spirit who’s crushed to death beneath an ice sculpture on the eve of her wedding, and Ashley (Lake Bell, of Boston Legal), the wannabe psychic who has designs on Kate’s onetime fiancé. Paul Rudd, as the unsuspecting veterinarian caught in the middle, is more of a calming presence.

Best known as the hopelessly deluded wingman from Judd Apatow comedies like Knocked Up and The 40-Year-Old Virgin, Rudd approaches his role with certain ironic detachment, as if distancing himself from the fallout. Surprisingly, it works – his sly, understated sarcasm strikes a nice balance with Bell and Parker’s overblown theatrics. He even lends a fleeting hint of subversive wit to the proceedings, though Jeff Lowell’s flaccid script undermines him early and often.

Rudd and Bell develop a playfully engaging banter that Lowell, who also directed, gives room to breathe, and Over Her Dead Body is a better movie for it. Bell radiates an irrepressible charm that Parker, charged with the thankless task of playing a spoiled, self-centered diva, is never given a chance to muster. The outcome of Ashley’s unusual courtship is never in doubt – she and Henry, who seems far too even-keeled to have fallen for an untamable shrew like Kate, are an easy match. The more pressing question is how much of Kate we’ll be forced to stomach.

Following her untimely demise, Kate returns to earth intent on saving her former fiancé from the dangers of moving on and promptly sabotages his burgeoning relationship with Ashley. Kate is the jealous type, defined by her selfish need to subvert Henry’s love life. What does she hope to accomplish? Who knows? Even Kate seems at a loss to explain her motives, but that’s to be expected in a movie that requires its characters to behave like lobotomized nincompoops.

Ashley, who masquerades as a psychic, can communicate with Kate, leading to sitcom-worthy situations that might have seemed funny on paper. Kate spies on her in the shower. She tricks her into an embarrassing scene at the gym. She even keeps Ashley awake at nights with tedious tales about her childhood pets. At some point, someone should have had the good sense to wonder whether anyone would want to watch this, much less find it amusing.