Hollywood's superhero foursome remained fantastic at the box office.

The 20th Century Fox sequel "Fantastic Four: Rise of the Silver Surfer" debuted as the No. 1 weekend film with $57.4 million, slightly surpassing the $56.1 million opening of "Fantastic Four" two years ago, according to studio estimates Sunday.

Among other new wide releases, a favorite teen detective had trouble finding an audience as the Warner Bros. mystery "Nancy Drew" premiered with a so-so $7.1 million to finish at No. 7.

Opening in narrower release was the Weinstein Co. thriller "DOA: Dead or Alive," an adaptation of the martial-arts video game that pulled in just $232,000.

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Playing in 505 theaters, "DOA" averaged a paltry $460 a cinema, compared to $14,499 in 3,959 theaters for "Fantastic Four" and $2,732 in 2,612 locations for "Nancy Drew."

The previous weekend's No. 1 movie, George Clooney and Brad Pitt's "Ocean's Thirteen," fell to No. 2 with $19.1 million. The Warner Bros. casino caper raised its 10-day total to $69.8 million, putting it on track to become the franchise's third $100 million hit.

Despite the big opening for "Fantastic Four," Hollywood revenues slipped for the third straight weekend. The top 12 movies took in $138.8 million, down 4 percent from the same weekend last year, when "Cars," "Nacho Libre" and "The Fast and the Furious: Tokyo Drift" led the box office with a combined $86 million.

The industry had a blockbuster May with "Spider-Man," "Shrek" and "Pirates of the Caribbean" sequels, but big films are not holding onto their audiences after huge opening weekends.

After a surge early this year, movie attendance has slipped to just a fraction ahead of 2006's, diminishing prospects of a record summer that many box-office analysts have predicted.

"We've seen our advantage over last year slowly being chipped away," said Paul Dergarabedian, president of box-office tracker Exhibitor Relations. "A lot of films are doing what these big summer movies do, open big and drop off fast."

The new "Fantastic Four" reunites the quartet of astronauts-turned-mutant superheroes, played by Ioan Gruffudd, Jessica Alba, Michael Chiklis and Chris Evans. This time, the comic-book heroes join forces with archenemy Dr. Doom (Julian McMahon) to take down the Silver Surfer, an emissary leading a planet-destroying entity to Earth.

The studio and filmmakers toned down the action so the sequel could earn a PG rating to broaden the audience to family viewers. The first "Fantastic Four" was rated PG-13.

"A lot of the superhero comic-book movies are sort of geared toward being darker and edgier. We think 'Fantastic Four' is a more family-friendly group of superheroes," said Chris Aronson, senior vice president for distribution at 20th Century Fox. "We wanted to make sure to cast a wide net and go after the family audience, and it worked."

Inspired by the Carolyn Keene mystery novels, the PG-rated "Nancy Drew" had less success with the female family audience. "Nancy Drew" stars Emma Roberts, niece of Julia Roberts, as the teen sleuth, who investigates the death of a movie star while visiting Hollywood.

Warner Bros. was hoping for solid weekday business from teenage girls to give a lift to the movie, said Dan Fellman, the studio's head of distribution. The movie was made on a modest budget of just over $20 million.

"We don't need a lot of money to come out ahead on `Nancy Drew,"' Fellman said.

Estimated ticket sales for Friday through Sunday at U.S. and Canadian theaters, according to Media By Numbers LLC. Final figures will be released Monday.

1. "Fantastic Four: Rise of the Silver Surfer," $57.4 million.

2. "Ocean's Thirteen," $19.1 million.

3. "Knocked Up," $14.5 million.

4. "Pirates of the Caribbean: At World's End," $12 million.

5. "Surf's Up," $9.3 million.

6. "Shrek the Third," $9 million.

7. "Nancy Drew," $7.1 million.

8. "Hostel: Part II," $3 million.

9. "Mr. Brooks," $2.8 million.

10. "Spider-Man 3," $2.5 million.

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