The Halloween frame shouldn’t be too scary for the biz in terms of B.O. returns as Lionsgate kicks off “Saw 3D,” launching today at 2,808 locations, of which more than 2,100 will be in 3D.

Despite the boost from higher 3D ticket prices, most B.O. pundits expect the last entry in the “Saw” series to debut in the low 20s, which could allow for another No. 1 showing for Paramount’s “Paranormal Activity 2” in its soph sesh. Last weekend, “Paranormal 2” opened wide to a boffo $40.7 million, and with generally positive aud response, it could see a better-than-average hold this weekend.

“Saw 3D” is the only wide release this weekend, though several specialty pics look to make an impression on the B.O. in limited release. That list includes Music Box’s final chapter in Stieg Larsson’s Millennium trilogy, “The Girl Who Kicked the Hornet’s Nest,” opening at 123 engagements.

Also in limited release, Samuel Goldwyn bows “Welcome to the Rileys,” starring Kristen Stewart and James Gandolfini, at 10 locations, while Magnet opens Gareth Edwards sci-fi scarer “Monsters” at two locales.

The Sunday timing of Halloween this year should bode well for the B.O., as the weekend is often soft at the box office, with moviegoers distracted by parties and trick or treating, when the big night falls on a Friday or Saturday.

Typically, Halloween has less of an impact at the foreign B.O. than domestically, meaning “Saw 3D” could start strong in debut markets like Australia, Russia, Mexico and the U.K.

Family-skewing holdovers, such as “Secretariat” and “Legend of the Guardians: The Owls of Ga’Hoole,” will fare best, with normal attendance Friday and Saturday, and then a more favorable drop Sunday.

For “Saw 3D,” Lionsgate said the Halloween launchpad is ideal given that the first installment kicked off the franchise Oct. 29, 2004, with a better-than-expected $18.3 million.

Lionsgate originally slated “Saw 3D” to bow last weekend but moved the pic after Par skedded “Paranormal Activity 2” for the same date. “Saw 3D’s” Halloween berth could prove beneficial, not only distancing the pic from “Paranormal 2” but also from Par’s “Jackass 3D.”

That pic outstripped expectations when it bowed to $50.4 million, with a cume to date of $91.8 million domestically.

As with “Jackass 3D,” Lionsgate hopes to use the 3D format to combat franchise fatigue with the seventh installment in the “Saw” tool chest. The “Saw” franchise has cumed more than $763 million worldwide, peaking in 2006 when “Saw III” brought in $33.6 million its opening weekend..

In an effort to help propel 3D interest with auds, Lionsgate created the illusion of a 3D eyeball in posters and online marketing materials.

“Saw 3D” should fall in line with most horror films, playing best to auds under 25, but Lionsgate said it expects to see an even split between men and women. Women made up 54% of the “Paranormal 2” overall opening weekend aud.

Holdovers like Summit’s “Red” and Warner’s “Hereafter” will seek to maintain their appeal to older auds in repeat frames. Entering its third weekend, “Red” has $47 million in domestic grosses, while “Hereafter” reached $15.1 million as of Wednesday. The Clint Eastwood pic expanded wide last weekend, with a muted $12.1 million from 2,181 locations.

Fox Searchlight mounts its first aggressive expansion for adult-driven biopic “Conviction,” with Hilary Swank and Sam Rockwell, to 565 locations, up from last weekend’s 85 runs. Pic has totaled just $524,480 since its debut Oct. 15.

“Saw 3D” also will compete with “Paranormal 2” for foreign ducats. The latter enters its soph sesh after launching day and date in 21 markets, with $22.3 million. Meanwhile, Universal’s 3D toon “Despicable Me” looks to continue benefiting from a successful counterprogramming bid, with overseas totals at more than $200 million.