IN A VINTAGE “Saturday Night Live” sketch, the Hulk and the Flash attend a superhero party where they mock the lesser-known Ant-Man, chortling over his ability to shrink to ant-size while still possessing “the strength of a human.”As Variety’s Gabriel Snyder and Pamela McClintock reported this week, many venerable movie franchises are “played out or aging,” triggering “a furious hunt for a replacement crop” of tentpole-worthy concepts. Yet when it comes to the perilous if potentially lucrative leap from comics page to bigscreen, Tina Turner misspoke in that “Mad Max: Beyond Thunderdome” song: Maybe we do need another hero. Special effects have evolved to the stage where it’s easy to “believe that a man can fly,” as the 1978 “Superman” promised on its memorable one-sheet. As a consequence, after years of uninspired, campy takes on beloved heroes, studios can “put something on screen that you never thought you could see with that level of realism,” as DC Comics editor Paul Levitz said in a recent interview. The irony, however, is that while virtually anything is now possible visually, there’s a dearth of recognizable characters capable of attracting a mass audience without provoking snickers among the uninitiated, making their elevation to “franchises” a super-human task. STRICTLY SURVEYING comic books, once you exhaust major stars at Marvel and Time Warner-owned DC Comics — Spider-Man, X-Men and the Hulk in the former’s arsenal; Superman, Batman and perhaps Wonder Woman in the latter — the pickings become decidedly slim. Marvel is taking another pass at the Hulk after Ang Lee’s overwrought stab, rolls out “Ghost Rider” next year and has “Iron Man” on the launchpad. Based on the track record of films like “The Punisher,” “Hellboy” and “Constantine,” none of these figure to give “Spider-Man” a run for his money. With most of big guns already discharged, that raises the specter of marching into battle with titles like DC’s the Flash and Green Lantern or Marvel’s Captain America and the Black Panther. And while those spandex-clad heroes might make the pulses of comic aficionados beat faster, they’re unlikely to flourish (outside the confines of Comic-con, anyway) a la “X-Men” or “Batman Begins,” regardless of how well they’re executed. No wonder Warner Bros. is planning a “Superman Returns” sequel despite its unspectacular box office flight: At least with the Man of Steel, people know what to expect and won’t giggle at the costume. Television isn’t necessarily a solution either. George Lucas has discussed bringing the next permutation of his “Star Wars” universe there, and NBC’s original concept “Heroes,” along with the CW’s “Smallville,” are performing well in that medium. Yet adapting certain second-tier characters to TV could be prohibitively expensive, while $100-million movies based on more obscure properties risks flops of “Howard the Duck”-sized proportions. THE CHALLENGE thus becomes whether the fantasy/sci-fi/superhero world — such fertile theatrical fare in the last decade — can unearth the next mega-concept or, more likely, exploit its legions of superheroes in less ostentatious ways. “We’re living in a time where the kind of stories we tell are in the heart of the culture,” Levitz said. “We have an astonishing catalog to bring to the screen.” Ah, but not a catalog of household names, and hence the studios’ dilemma. Wisely, Marvel and DC are pursuing a middle ground with direct-to-DVD projects, such as Marvel’s animated “Ultimate Avengers” movies, an adult take on the squabbling superhero team. DC is similarly plunging into that realm with animated versions of “Superman: Doomsday,” “Teen Titans” and “Justice League: New Frontier,” all chronicling wildly popular comic storylines that might warrant a quizzical look from mere mortals. The goal, says DC Comics senior VP of creative affairs Gregory Noveck, is to “appeal to core fans and not-so-core fans,” allowing Warner Bros. to “take more advantage of DC as a brand and a library.” Live action is also on the drawing board, and in a best-case scenario, Noveck says, characters that pop on DVD will help point the way toward which might be developed as features. If not, they can profitably deliver doubles or singles, without having to gamble on swinging for the fences. As for true home-run franchises, though, that still looks like a job for Superman.