Vin Diesel's spy thriller XXX holds on to the top spot at the North American box office beating competition from crop circles and women surfers.

Mel Gibson vehicle Signs, the tale of a farmer fighting aggressive aliens, stayed at number two taking $19.5m (�12.7m) to XXX's $23m (�15m), according to studio estimates.

Blue Crush, starring Kate Bosworth, Michelle Rodriguez and Sanoe Lake as surfers in Hawaii made a strong debut at number three with $15.2m (�10m).

US and Canada top five

1. XXX 2. Signs 3. Blue Crush 4. Spy Kids 2 5. Austin Powers in Goldmember Source: Exhibitor Relations

But Eddie Murphy's latest comedy, The Adventures of Pluto Nash, flopped badly in its first weekend taking just $2.15m (�1.4m) despite a $90m (�58.4m) budget.

The sci-fi comedy came in at number 10 and not been screened in advance for the press, usually a sign the studio does not rate the movie.

"Unfortunately, every studio at some point has to face disappointing results from one of your films," said Dan Fellman, head of distribution for Warner Brothers, which released Pluto Nash.

"You only hope they're few and far between."

Revenue record

With a limited release, Gwyneth Paltrow's romance Possession started with a respectable $1.6m (�1m).

Sony, whose recent releases include Spider-Man, Men in Black II, XXX and Mr Deeds, has now broken the Hollywood record for highest one-year revenue for a single studio.

The studio beat the previous record of $1.27bn (�824m), also set by Sony in 1997, when its hits included Men in Black, Air Force One and My Best Friend's Wedding.

The disadvantage of late summer is it's hard to get a big opening

Jeff Blake Sony

"This has been a dream year for the studio," said Amy Pascal, chairman of Sony's Columbia Pictures.

Sony still has a menu of strong releases to come before the end of the year.

Those likely to do well include Adam Sandler's animated 8 Crazy Nights, Sandler and Emily Watson in Punch Drunk Love, Murphy and Owen Wilson in I Spy and Jennifer Lopez in Maid in Manhattan.

The studio will also expect to build on the $84.9m (�55.2m) already taken by XXX, which has confirmed Diesel's status as Hollywood's big new action star.

Up against it next week are Al Pacino's Hollywood satire Simone, the Elizabeth Hurley and Matthew Perry comedy Serving Sara, and prison boxing tale Undisputed, starring Wesley Snipes and Ving Rhames.

Less competition

"The disadvantage of late summer is it's hard to get a big opening because people are less in tune for going to the movies," Sony distribution head Jeff Blake said.

"The advantage is there's a lot less competition."

Overall, Hollywood revenues slipped for the fifth straight week after months of surging business.

The top 12 films took in $101.4m (�65.8m), down 2% from the same weekend last year.

Summer revenues still remain about 5% ahead of the record set last year.

Hollywood remains on track to break 2001's year-long box-office record of $8.4bn (�5.45bn), said Paul Dergarabedian, president of Exhibitor Relations, which tracks ticket sales.