It’s T-minus seven days to the arrival of “The Simpsons Movie,” and fans around the world are speculating: Just what is the film going to be about, anyway?

Steeped in the kind of secrecy one typically associates with nuclear codes and the identities of CIA operatives, few leaks have sprung about the film’s story, or its possible surprises. But with the franchise now in its 18th year, one can take some clues from what it has done on the small screen to anticipate a bit of what might happen on the big screen.

Above all, the creators of “The Simpsons” have consistently given life to a hilarious, sprawling Springfield universe that revolves around their core family. Unlike most sitcoms, which focus on the same handful of goofs every week and take place in the real world, each “Simpsons” episode brings with it the possibility of seeing any of 50, or maybe it’s closer to 100, characters make brief cameos.

Talk to 20 “Simpsons” fans and you’re bound to hear about 20 different favorite characters. It’s a creative accomplishment that 20th Century Fox is banking on in hopes of bringing out every “Simpsons” fan, past and present, to the theater next week. In one of the movie’s most ubiquitous TV spots, young Ralph Wiggum — the dimwitted son of Springfield’s police chief who once said his lifelong dream was to become a fire truck — gets more screen time than Homer Simpson, as he sings along (off-key and out-of-rhythm) with the Fox theme.

“That ad in particular shows some of what they are trying to do with this movie — a movie that few of us know how well it will do at the box office,” a box office analyst with Exhibitor Relations, Chad Hartigan, said. “They’re so confident in their characters, and the world they created, that they are creating ads with only their minor characters from the show. They are literally banking on the popularity of the wider Springfield universe.”

But which sliver of that universe will get the feature film treatment — and who will be left out? Here’s a look at the dozen “Simpsons” semi-regulars who deserve the promotion:

DUFFMAN
Beer Mascot

“Are you ready to get Duffed? … OOH YEAH.”

All the consumerism of a capitalist society, all the classic American beer worshipping, wrapped in a single package. A 24-hour party guy with cool shades and a beer utility belt, Duffman is the partier who shows up routinely throughout Springfield, girls in tow and brews in hand. To Homer Simpson, he is nothing short of a God, but to the many “Simpsons” writers who have evoked Duffman through the years, he is more than a symbol of Homer’s beer worship — he’s the ready-to-use icon of marketing run amok, the TV rock star every guy with a beer gut imagines he could be.

KODOS & KANG
Space Aliens

“We’ve reached the limits of what rectal probing can teach us.”

Green, gangly, drooling, and cackling all the time, Kodos and Kang are the recurring aliens of the series’ annual Halloween episodes — always orbiting Earth, determined to subordinate the human race. In perhaps their most brilliant performance, they take over the bodies of both the Republican and Democrat presidential candidates and try fruitlessly to placate the people: Kang: Abortions for all! Audience: BOO! Kang: Okay … abortions for none! Audience: BOO! Kang: Hmm … Abortions for some, tiny American flags for others! Audience: YAAY!!!”

HANS MOLEMAN
Sad Sack

“Today, part four of our series of the agonizing pain in which I live every day.”

The short, wrinkled, crackly-voiced Hans Moleman is easily the most pathetic character in Springfield, a man resigned to his loserdom who gets hit in the groin with a football and who winds up locked in a closet or left in a parked car. He is the embodiment of everything that is pitiable, the guy we can’t stop laughing at while secretly feeling sorry for. If someone’s going to make a mistake, or get left behind in “The Simpsons Movie,” here’s your guy.

GIL GUNDERSON
Failed Salesman

“Let’s talk rust-proofing. … Shut up, Gil. Close the deal … close the deal!”

A tribute to Jack Lemmon’s over-the-hill salesman from the movie version of David Mamet’s “Glengarry Glen Ross,” Gil is the salesman incapable of making a sale, his tie always loosened, his hair always a mess and his surething always fizzling in front of his eyes as his insecurity reigns supreme. His wife has surely left him by now.

COMIC BOOK GUY
Comic Book Store Owner

“Worst episode ever.”

The legions of die-hard “Simpsons” fans who have memorized entire episodes no doubt feel a special affinity for the bloated, bearded Comic Book Guy, who not only prides himself on being a nerd, but who uses his nerd knowledge to mock others in his store.

He’s the guy who fawns over Catwoman, who shows up at movie premieres of his favorite comics dressed as the hero, and who groans in frustration as his downloaded picture of Captain Janeway (that’s the female captain from the series “Star Trek: Voyager” for you amateurs) stalls due to his dial-up connection.

DR. NICK RIVIERA
Surgeon

“The gloves came free with my toilet brush.”

He asks people to call him “Dr. Nick,” and therein lies the problem: The terms “doctor” and “casual” don’t often go together. Dr. Nick, who makes English an adventure, can’t provide credentials when he enters the O.R., and his greatest asset is that he’s always offering bargain-basement prices. Alas, his standards are as low as his expertise. Less than a confident sign: As you start to go under, Dr. Nick points to your stomach and asks: “What the heck is that?”

PROFESSOR FRINK
Mad Genius

“There was trouble at the lab with the running and the exploding and the crying when the monkeys stole the glasses off my head.”

Professors are rarely the hit of the party. Genius begets awkwardness, and few characters on “The Simpsons” are as socially inept as Professor Frink. Inspired by Jerry Lewis’s nutty professor, Frink rambles incoherently through run-on sentences with “yoinks” and “fleyvens” while squinting through thick glasses and describing one of his many robotic creations. But he’s usually unable to explain quite what he’s doing and, as is so often the case, where the experiment went wrong.

DISCO STU
Dancing Machine

“Disco record sales were up 400% for the year ending 1976? If these trends continue … ayyyyy!”

A stereotype caught in the wrong decade, Disco Stu doesn’t quite fit into the digital age — and doesn’t care. Always sporting sunglasses, an afro, and bell-bottoms, he’s the man who likes to think he has all the moves down — both with women and on the dance floor — unaware of American life post-Carter.

LUNCHLADY DORIS
Cafeteria Worker

“More testicles means more iron.”

No show featuring grade schoolers would be complete without the horrors of the school cafeteria, and what cafeteria would be complete without a rough and gruff lunch lady to offer the children a daily helping of mystery meat? Lunchlady Doris, who takes the stereotype one step beyond, is always chomping on a cigarette, looking down at the children through saggy, dismissive eyes, and talking openly about the Grade-F meat essential to her cuisine.

RAINIER WOLFCASTLE
Action Star

“Mein bratwurst has a first name, it’s F-R-I-T-Z. Mein bratwurst has a second name, it’s S-C-H-N-A-CK-E-N-P-F-E-F-F-E-R-H-A-U-SE-N.”

Before he was a re-elected governor of California, Arnold Schwarzenegger was the chiseled face and garbled voi ce that became synonymous with the action movie genre, and in “The Simpsons,” Rainier Wolfcastle is that same mindless, blood-soaked movie icon. In one of Rainier’s earliest appearances, Homer Simpson is visiting a video store and stares up at the TV screen showing the new Wolfcastle film — the hero delivering his lines in a drawl before blowing away the bad guys. Not that Homer seems to mind — he cheers Rainier on, as only an escapism-seeking American with low expectations can.

KENT BROCKMAN
News Anchor

“…And the fluffy kitten played with that ball of string all through the night. On a lighter note, a Kwik-E-Mart clerk was brutally murdered last night.”

Anyone who’s ever worked in local television can tell you about how the nightly news is insanity masked as something serious and officious — a few reporters, a few writers, and a newscaster who is supposed to project the gravitas of an omniscient news deity. All of this makes Kent Brockman the hilarious yin and yang of local TV news, complete with a hard-hitting voice, a fierce gaze, and a mind devoid of anything resembling solid news judgment.

When it looks like Springfield’s been invaded by giant mutant ants, he sheepishly welcomes the new overlords; when he realizes it was all a misunderstanding, he tears down the giant ant poster on the newsroom wall and calmly corrects the record: “See you after the movie.”

ssnyder@nysun.com