EW scopes out the annual San Diego convention that's bringing Hollywood to its knees, with fans sure to drool over presentations for ''Iron Man,'' ''Superbad,'' J.J. Abrams' ''Star Trek,'' Tim Burton's ''Sweeney Todd'' and more

Cannes has Brad Pitt and Angelina Jolie on the Croisette. Sundance has Robert Redford on the slopes. And Comic-Con? It’s got Klingons in Renaissance costumes running around downtown San Diego.

From July 26 to 29, tens of thousands of devoted pop culture fans will descend upon Southern California for the largest gathering of sci-fi and fantasy enthusiasts held on this or any planet. It’s been called Woodstock for geeks, but these days it’s a whole lot more. The annual Comic-Con convention is now one of the most critical industry events on the calendar, as important to Hollywood as any festival in France or Utah.

What started in 1970 as a small comic-book lovers’ conclave (just 300 people made it to that first meeting) today draws more than 120,000 people. And it isn’t just fanboys attending the convention’s screenings, parties, and panel discussions; among the crowd this year will be Clive Owen (who’ll build buzz for Shoot ‘Em Up), Jessica Alba (The Eye), Robert Downey Jr. (Iron Man), Edward Norton (The Incredible Hulk), and Judd Apatow (Superbad), along with hordes of producers, directors, and writers, like J.J. Abrams, who may announce some of his casting picks for the upcoming Star Trek reboot. For certain genres — the ones involving superheroes, aliens, warriors in leather codpieces, and comic-book characters — there is now no greater launching pad than the floor of the San Diego Convention Center. These days, even some surprising genres — like Westerns (3:10 to Yuma), music-industry satires (Walk Hard), and Broadway musicals (Tim Burton will share clips from his upcoming adaptation of Sweeney Todd) — are finding their way to Comic-Con.

”It’s the golden age of geekdom,” says frequent Comic-Con conventioneer Brad Meltzer, a novelist and comics writer. ”Hollywood has figured out the location of the supergeek clubhouse. They’ve jimmied the locks, moved in, and spruced the place up. And we’re sort of sadly and pathetically okay with it, because they bring lots of hot actresses and nice film clips.”

NEXT PAGE: ”I’d much rather spend money on Comic-Con than on a splashy premiere the day before my movie opens.”