LOS ANGELES (Reuters):

If it's Halloween, it must be time for the Saw horror franchise to scare up the top spot at the North American box office.

Saw IV, the latest instalment in the annual series about a sadistic serial killer named Jigsaw, sold about $32.1 million in tickets during the weekend, according to studio estimates issued on Sunday.

Opening at Number 2 was the Steve Carell comedy Dan in Real Life with $12.1 million. Last weekend's champion, the vampire thriller 30 Days of Night, fell to Number 3 with $6.7 million.

Saw IV, opened about $1.5 million lower than its predecessor this time last year, breaking a pattern that had seen each new instalment open more strongly than the previous one. But most franchises are usually running on fumes by the time the fourth iteration hits the screens, a fate that evidently has yet to befall Saw.

Saw IV marks the second chart-topper in three weeks for indie studio Lionsgate, a unit of Lions Gate Entertainment Corp., following Why Did I Get Married? Film-maker Tyler Perry's romantic comedy drama fell two places to Number 5 with $6.3 million, taking its haul to $47.3 million.

Dan in Real Life, from Walt Disney Co.'s Touchstone Pictures, stars Carell as a widowed family-advice columnist who falls for his brother's girlfriend, played by Juliette Binoche. Its opening was within expectations and Disney said it scored well in exit interviews.