Los Angeles ? “Scooby-Doo,” where are you? On top of the weekend box office.

The big-screen update of the Hanna-Barbera cartoon, starring Matthew Lillard, Freddie Prinze Jr., Sarah Michelle Gellar, Linda Cardellini and a computer-animated Great Dane, took in $56.4 million to debut as the No. 1 film, according to industry estimates Sunday.

“The weekend really went to the dogs,” said Paul Dergarabedian, president of box-office tracker Exhibitor Relations. “In these trying times, what could be more escapist than ‘Scooby-Doo,’ which is so fun and lighthearted?”

Matt Damon’s “The Bourne Identity,” a spy thriller about a deadly amnesiac agent, opened in second place with $27.5 million.

“Windtalkers,” starring Nicolas Cage and Adam Beach in a drama about Navajo Indian codetalkers in World War II, premiered a weak third with $14.5 million.

The espionage tale of Damon’s buddy Ben Affleck, “The Sum of All Fears,” slipped to fourth place after two weekends as the top film, taking in $13.5 million and pushing its 17-day total to $84.5 million.

The industry continued its upward trend, with the top 12 movies grossing $160 million, nearly 25 percent higher than the same weekend a year ago. Revenues for 2002 are running about 22 percent ahead of the record $8.4 billion last year.

“Scooby-Doo” was one of Hollywood’s few successes in adapting a TV cartoon to the big screen. “The Flintstones” did well, but the prequel “The Flintstones in Viva Rock Vegas” was a commercial dud.

Other recent cartoon adaptations flopped, including “Josie and the Pussycats” and “The Adventures of Rocky and Bullwinkle.”

“Scooby-Doo is a character that obviously reaches a much wider audience than most cartoons,” said Dan Fellman, head of distribution for Warner Bros., which released “Scooby-Doo.” “The audience was Scooby fans from 8 to 80. We had kids, we had adults. We had everybody.”

Estimated ticket sales for Friday through Sunday at North American theaters, according to Exhibitor Relations Co. Inc. Final figures will be released Monday.

1. “Scooby-Doo,” $56.4 million.

2. “The Bourne Identity,” $27.5 million.

3. “Windtalkers,” $14.5 million.

4. “The Sum of All Fears,” $13.5 million.

5. “Divine Secrets of the Ya-Ya Sisterhood,” $9.8 million.

6. “Star Wars: Episode II: Attack of the Clones,” $9.2 million.

7. “Spider-Man,” $7.4 million.

8. “Bad Company,” $6.1 million.

9. “Spirit: Stallion of the Cimarron,” $5.5 million.

10. “Undercover Brother,” $4.6 million.