Tobey Maguire as Spiderman

Kirsten Dunst believes 'Spiderman 4' will be a flop if she and Tobey Maguire don't star in it.The actress - who plays Mary Jane Watson, the love interest of the superhero's alter-ego Peter Parker, in the hit movie series - insists any attempt to continue the franchise without her, Tobey - who plays the web-slinger - and director Sam Raimi would be a box-office disaster. She told Entertainment Weekly: "Audiences aren't stupid. It'd be a big flop without me, Tobey or Sam."Dunst is doubtful Sony Pictures would want to make a fourth movie if Raimi wasn't at the helm.She added: "That would really not be the smartest move. But they already know that." Dunst and Maguire have both distanced themselves from a fourth movie, with the pair admitting they would like to pursue other roles. Maguire said: "I feel like this film is kind of a natural conclusion to alot of stuff that's happened in the first two movies. It kind of feels likea natural trilogy. I'm not going to make more just because they've been successful."Raimi is rumored to be in the running to direct the film version of J.R.R.Tolkien's classic novel 'The Hobbit', which is a prequel to the 'Lord of the Rings' books. He is said to be first choice if New Zealand filmmaker Peter Jackson, who directed the Oscar-winning 'Lord of the Rings' films, turns the project down. Meanwhile, 'Spiderman 3' had its world premiere in Tokyo yesterday the other day. Maguire took his jewellery maker fiancée Jennifer Meyer and their baby daughter Ruby along to the glitzy event because he can't bear to be apartfrom them.The actor - who braved the rain to walk down the red carpet with his co-star Dunst - said: "I love being a dad. I didn't want to be away from them and Ididn't want my fiancée Jen to miss this. It's a pretty eventful moment and Iwanted to be with them. I haven't been away for a night yet."After several premieres across the globe 'Spiderman 3' opens worldwide on May 4.