SANTA MONICA, California — Tobey, meet Topher.

Marvel Studios Chairman/ CEO Avi Arad announced Thursday (May 19) that Topher Grace is joining the cast of the upcoming blockbuster "Spider-Man 3." Scheduled for release on May 4, 2007, the third movie in the "Spider-Man" saga will unite the "In Good Company" star with previously announced participants Tobey Maguire, Kirsten Dunst, James Franco and Thomas Haden Church.

"First we had Tom, [now] we have a very interesting guy joining the cast," said a smiling Arad at MTV's West Coast headquarters. "His name is Topher."

Arad said the presence of Grace — whose role is not yet known — will continue a Marvel movie tradition of casting actors who might not immediately come to mind to portray comic book characters. "That's the fun in this universe. We have a good rule about this: There is no against type. You find someone who brings the role of the individual, not the costumed individual, to life. Before we put Tobey Maguire as Spider-Man, if you had said Peter Parker ... if you just did a [survey], I don't think you would have heard too many Tobey Maguires coming to mind."

While Arad and Marvel continue to refuse comment on which characters Grace and Church will play, the 57-year-old Arad did hint that Grace had been cast contrary to the typical nice-guy roles that have made him a household name. "That's a good question," is all he'd say when asked for the identity of Grace's alter ego. "Just before I came here, we were all on the phone with [other Marvel executives] and I said to them, 'Are you nuts? We can't tell anybody who he is. This is all the fun. The fun is figuring out.'

"That's how you have to look at it," Arad said about keeping the fans waiting. "Topher, we believe, is joining the ranks of the incredible actors."

With Church, Arad remains similarly tight-lipped, side-stepping fan rumors that the Oscar-nominated "Sideways" star will take on the villainous role of Sandman. "I don't know," he smiled. "[Church is] all confused, you know, these Texans. Yes, of course he [knows who he's playing]. You know what? The movie is 2007; to be straight about it, it's taking all the fun away. I just love the fact that there are such guessing games going on."

In a statement from Marvel, series director Sam Raimi expressed similar enthusiasm for the casting news. "I couldn't be more excited about the direction we are taking the continuing adventures of Peter Parker. Topher Grace is an extraordinarily talented actor and will be perfect for the complexities of the role we are developing."

While discussing the film, Arad also dismissed rumors that the next two "Spider-Man" movies will be filmed simultaneously, following the cost-cutting formulas of the "Matrix" or "Pirates of the Caribbean" sequels. "Not true," he insisted. "No, it doesn't make sense ... I don't believe it. I don't believe you really save money. What you do, in essence, is you ensure that you book your stars for long enough."

Still, he said excitedly, Peter Parker's next adventure will be the most ambitious one yet. " 'Spider-Man 3' has to be bigger than '1' and '2,' " Arad said, "So storywise it's already bigger, the characters in it are already bigger ... it will already be a handful to [complete it by] May 2007."

More than $1.5 billion worldwide has been taken in by the "Spider-Man" film franchise with its first two installments. "Spider-Man 3," which will be working off a script penned by second-installment writer Alvin Sargent, begins filming early next year.

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