K-PAX, the Universal drama starring Kevin Spacey as a man who claims he's an alien, opened at the top of the North American box office with an impressive estimated three-day gross of $17.5m.

The movie was co-financed by Intermedia, which screened it to international buyers for the first time at London Screenings last week. Budgeted at $48m, the film was directed by the UK's Iain Softley and co-stars Jeff Bridges, Alfre Woodard and Mary McCormack. Reviews were decidedly mixed.

K-PAX beat out Warner's horror movie from Dark Castle Entertainment 13 Ghosts, released to tie in with Halloween, which took a strong $15.7m. A mid-budget remake of the William Castle classic, the film is the second Dark Castle movie to open over Halloween after last year's profitable House On Haunted Hill.

Another Halloween title, New Line's horror movie Bones starring popular rapper Snoop Dogg grossed only $3.8m over five days after opening on Wednesday.

Also performing disappointingly was Miramax Films' romantic comedy On The Line which featured N Sync pop stars Lance Bass and Joey Fatone and opened at number 11 with $2.3m

The box office was up 3.3% from the same weekend last year, and should remain buoyant next weekend with the high powered openings of Jet Li actioner The One from Revolution/Columbia, John Travolta thriller Domestic Disturbance from Paramount and the long-awaited animated movie Monsters Inc from Disney/Pixar.

ESTIMATED TOP TEN US OCT 26-28

Film (Distributor)/International distribution/Estimated weekend gross/Estimated total to date

1 (-) K-PAX (Universal) Intermedia $17.5m --

2 (-) 13 Ghosts (Warner Bros) Warner International $15.6m --

3 (1) From Hell (20th Century Fox) Fox International $11.3m --

4 (2) Riding In Cars With Boys (Columbia) Columbia TriStar $6m $19.1m

5 (3) Training Day (Warner Bros) Warner/Village Roadshow $5.1m $65m

6 (4) Bandits (MGM) Hyde Park/Fox International $5m $32.1m

7 (6) Serendipity (Miramax) Miramax International $3.9m $40.1m

8 (5) The Last Castle (DreamWorks SKG) UIP $3.7m $13m

9 (-) Bones (New Line) New Line International $2.95m $3.8m

10 (7) Corky Romano (Buena Vista) BVI $2.9m $20.2m