Horror film Saw IV has sealed the biggest autumn opening at the US box office, taking $20 million more than the second most popular film of the weekend.

The fourth instalment in the horror franchise grossed an estimated $32.1 million from 3,183 US locations, while Disney comedy/drama Dan in Real Life scooped $12 million from 1,921 sites.

According to Variety, the enduring popularity of the Saw franchise should see its box office receipts surpass the $500 million mark at the worldwide box office this week.

Though the fourth film's opening weekend takings fell just short of Saw III's domestic opening of $33.6 million, it edged ahead of the $31.7 million opening figures for Saw II.

After vampire horror 30 Days of Night debuted at the number one spot last weekend, Steve Rothenberg, president of distribution for Saw's production company Lionsgate, said: "Horror is still alive and well."

He added: "Saw fans have proven their loyalty to the franchise once again by giving it the biggest opening of the fall season."

Exit polls for the fourth movie – directed by Darren Lynn Bousman and seeing Tobin Bell reprise his role as Jigsaw – revealed that 90 per cent of the audience for Saw IV had seen all the films in the franchise.

29/10/2007 08:13:48