When Tim Burton and Johnny Depp decided, “Oh, wouldn’t it be fun to make a movie out of the campy ’60s TV show ‘Dark Shadows’,” the correct response should have been the following three words: “Wild Wild West.”

Apparently no one had the stones to say that to Burton or Depp, whose inflated reputations rest on their box-office clout, much more than their artistic vision. And so we have “Dark Shadows,” as dreary a big-budget extravaganza as you’re likely to see this year (unless Michael Bay springs a movie on us unexpectedly).

“Dark Shadows” is all the argument you need for staging some sort of couples’ intervention on Depp and Tim Burton. Yes, I know – they made “Charlie and the Chocolate Factory,” “Ed Wood” and “Sweeney Todd,” all worthy films. On the other hand, they made the middling “Sleepy Hollow,” the execrable “Alice in Wonderland” and now this piece of mirthless kitsch. So it’s really a wash, wouldn’t you say? Time to move on and stop enabling this kind of pop-culture junk.

Big, loud, lavish and flat, “Dark Shadows” was written by Seth Grahame-Smith, who came up with the one-joke idea of mash-ups blending classic literature and history tales blended with horror-movie tropes, like “Pride and Prejudice and Zombies.” The witless script here doesn’t bode well for Grahame-Smith’s screen adaptation of his own “Abraham Lincoln: Vampire Killer.”

That’s because virtually all of the jokes in “Dark Shadows” are DOA. They’re either trite (an 18th-century vampire wakes up in 1972 and is mystified by cars and TV – how clever) or simply flat (let’s have that vampire say “Kiss my ass” in formal 18th-century language). And the horror? Forget it – too jokey. And the jokes? Not nearly jokey enough.

Tricked out like a gothic romance, “Dark Shadows” chronicles the early plight of Barnabas Collins (Depp), scion to a rich fish-cannery family in pre-Revolutionary War Maine. The family is so dominant that the town is called Collinsport; their lavish mansion is called Collinwood. But Barnabas runs afoul of a witch named Angelique (Eva Green), whose love he doesn’t return. So she kills his parents, casts a spell on the woman he loves (Bella Heathcote) that causes her to throw herself off a cliff – and then turns Barnabas into a vampire and rats him out to the townsfolk, who entomb him alive.

(The vampire lore is incredibly half-assed here. Aside from the fact that Barnabas becomes a vampire through a witch’s spell – as opposed to being bitten and turned by another vampire – there’s the whole on-again, off-again nature of his relationship with daylight. Not that that’s this movie’s biggest problem, but just saying.)

When Barnabas is accidentally released, it’s 1972 (oh Tim, how daring – making fun of lava lamps and the fashions of that earlier era!) and the Collins family is on the skids. What’s left of his family, dominated by matriarch Elizabeth (Michelle Pfeiffer) and her ne’er-do-well brother Roger (Jonny Lee Miller), inhabits Collinwood in virtual poverty, or as much poverty as it takes to run a mansion with a pair of obviously cut-rate servants. The Collins’ fish cannery is in ruins and the town is dominated by the cannery run by the still lively Angelique. So Barnabas – now a stunning shade of fish-belly white – moves back in to Collinwood to help the family revive the business to get revenge once and for all on Angelique.

Stale? The plot is positively moribund and the writing is no better. There are any number of barely sketched characters, from the clichéd drunk of a houseman (Jackie Earle Haley) to Elizabeth’s sullen teen daughter (Chloe Grace Moretz) to a live-in shrink (Helena Bonham Carter). There were probably other actors with three names clamoring for roles but, mercifully for their careers, they aren’t in this film.

“Dark Shadows” isn’t the worst movie ever made. It probably won’t even be the worst movie of the year. And that’s the best I can say about it. Watching it is like being told a weak joke that you already know.