People sometimes complain that Hollywood product panders to the audience, but actually, middling entertainment such as “Fool’s Gold” feels mostly indifferent to your existence. This bland romantic comedy-adventure, starring two half-hearted semi-stars and some treasure, unfolds slowly but surely, never too eager to please, the mediocrity washing over you like the sea. It’s not even the best at being the worst.

But neither is there any mustache-twirling pleasure to panning inevitabilities such as “Fool’s Gold” (nor should there be). On the contrary, it would be delightful to report that this tale of a divorced couple finding loot and love in the Caribbean despite a dastardly Rastafarian is the “His Girl Friday” or “When Harry Met Sally” of waterlogged Spanish bullion. However, the evidence does not exist to support this conclusion or ones like it.

Vapidly cheery Matthew McConaughey bounds around shirtless as Finn, a beach-bummy treasure hunter who is late to his own divorce proceedings. Fed-up Tess (Kate Hudson) kicks herself for having married him (although, in a pitiful running joke, she does not regret the sex). Billionaire Nigel Honeycutt (Donald Sutherland) employs Tess on his yacht and putters about waiting to launch the film’s plot through happenstance. His airhead heir Gemma (Alexis Dziena) obliges by losing her hat, which is snatched from the breeze by the quick-thinking Finn.

After intriguing Tess’s very bored but very rich boss, Finn draws his ex-wife into one last hunt together: the booty being, irony of ironies, the wedding dowry lost at sea in 1715 by King Philip II of Spain. Taking a cue from “National Treasure,” the educated, undynamic duo cheerfully free-associate their way through history and maritime geography (which, though the movie doesn’t seriously make the claim, bears a kernel of truth, in a gold-rich Spanish shipwreck dating from the same year that was in fact found in the 1960s).

But lest that arouse your interest, how about those antic supporting players? Representing Slavic accents and frantic mugging is Finn’s sidekick Alfonz (Ewen Bremner), while thuggish villainy and disconcerting bursts of violence come courtesy of white-suited gangster Bigg Bunny (Kevin Hart) and his crew. Last, traversing the accents of many English-speaking territories is rival treasure hunter Mo Fitch (Ray Winstone? yep, Ray Winstone), who fades away until a finale demands another warm body.

Everyone gets a good line or two, and Mr. Sutherland’s faintly incredulous readings let slip some dry wit, but director Andy Tennant, who let Will Smith steer “Hitch” to millions, is mostly King Midas in reverse here. The sunglazed posters for “Fool’s Gold” point better to the cruise-line stopover attractions that receive real care. Azure shallows, snazzy water transport, a tiny church on a promontory, notable rock formations — sure, easy on the eyes, and in another time, say, the 1910s, maybe enough for a movie.

But you have to hand it, or something at any rate, to Mr. McConaughey, who pulls his buff, chest-waxed weight despite Ms. Hudson’s understandably dispirited performance.

The two don’t charm or mesh any better than they did in their previous teaming for “How to Lose a Guy in 10 Days,” but the endearing bongo-bopper has the earnest focus of a chatty drunken acquaintance at a party who inexplicably holds your attention until you snap to your senses, realize you are sufficiently less drunk, and leave.

We’ve stumbled into an especially soul-sucking February weekend that features not only a movie starring Paris Hilton (“The Hottie and the Nottie”) but, via Ms. Dziena’s Gemma, an heiress character combining the fashion-forward egocentric oblivion of Ms. Hilton with the gabby eternal pubescence of an Olsen twin. “Fool’s Gold” is not quite so contemptuous in pocketing your hard-earned wage, but there’s still the sense that, to paraphrase Pogo, we have met the fool and he is us.