The new thriller “Dragonfly” contemplates several age-old spiritual questions: Is there a world after this one? Does this world have the power to communicate, control, and possibly influence our lives? Can hope and faith lead to truth?

Despite these complex, heavy examinations into the great beyond, the film’s most intriguing and complex query exceeds cosmic befuddlement: how many bad movies can Kevin Costner make in a row?

Please do not simply dismiss this crucial matter as a reviewer’s weak attempt at humor. It is an important issue that must be taken seriously. In the past, there were at least ways to explain this incredible penchant for failure: “Waterworld” battled rigorous ocean locations; “The Postman” tried too hard to replicate Kevin’s “Dances With Wolves” success with an exhaustive running time; and “3000 Miles to Graceland” could at least hide behind the actor’s childhood adoration of Elvis Presley and guns.

But with “Dragonfly,” there are no more excuses. This “thriller,” directed by Tom Shadyac (“Ace Ventura: Pet Detective”), fails not because of circumstantial maladies or Kevin’s bad instincts. Instead, its painful resolve to meld personal exploration with traditional suspense muddies both endeavors. With its sluggish pace and lack of direction, “Dragonfly” joins last month’s similarly bug-themed debacle “The Mothman Prophecies” (which I also had the joyful task of reviewing) as evidence that the suspense genre needs resuscitation.

The first sign of disaster comes in the film’s opening moments: Dr. Joe Darrell (Costner) is desperately talking to his wife, Emily (Susanna Thompson), a Red Cross worker trapped in a violent storm in a small South American village. This exchange is meant to both provide information for the viewer and draw us into the conflict, yet it accomplishes neither. The dialogue is too frantic and unwieldy, and it sets the stage for the melodramatic histrionics to come. Furthermore, Joe’s declaration to his wife that he is “not going anywhere until this is over” is said with a startling lack of feeling. It would seem that intense determination is not in Kevin’s repertoire.

Emily dies moments later when the man driving her bus decides to creep along the edge of an unsteady cliff. The rest of the film tracks Joe’s struggle to cope with both his unbearable grief (an emotion Kevin also seems at a loss to play) and his strange sense that Emily is trying to communicate with him from the dead.

While it may be easy to merely indict Costner, the unbearable script must share culpability. The writers are particularly impressed with the annoying dragonfly ploy with which they mercilessly pound the viewer. As the film’s awkward flashbacks inform us, Emily had a dragonfly tattoo on her back; revealed with even more subtlety, she wants to be a dragonfly in her next life. The symbol is meant to tie the film’s real and spiritual worlds in a creepy, slightly macabre bow. If “The Mothman Prophecies” taught us anything, it was that insects do not offer an effective representation of otherworldly hopes and fears.

That “Dragonfly’s” director also taught Jim Carrey how to talk out of his ass helps explain the film’s absence of nervy tension and heartfelt sensibility. Yet more importantly, the script neglects its supporting players. Everyone from Joe’s indistinguishable college buddies to his supportive neighbor (Kathy Bates) fails to contribute dramatic fuel or add color and texture. Instead, they exist simply to provide the film with some alternatives to Joe’s anguished walks through his dark, tormented home.

Although seeping with slightly enjoyable cornball melodrama and sweeping music, the film’s conclusion cannot displace these structural deficiencies. Because of its relative vitality, this requisite “surprise ending” actually ends up being the film’s crucial downfall. Movies like “The Sixth Sense” became famous for their “did you see that?” finales, and “Dragonfly” mistakenly assumes that its conclusive moments can compensate for the previous 90 minutes’ incomprehensible inertia.

Some final advice for Kevin: fire your agent, take a year off, and reinvent yourself as a character actor by taking on small roles in interesting, innovative, and independent films. Because the only thing that could possibly be worse than “Dragonfly” is “Dragonfly 2: Return of the Bug”.