"If it's Halloween, it must be Saw," the ads for previous Saw movies declared, and this Halloween weekend is no exception, despite the series dulling with the previous entry, Saw VI. The seventh installment, Saw 3D, arrives as the sole new nationwide release on around 3,500 screens at 2,808 locations, marking the second-smallest release of the series, behind the first Saw. Paranormal Activity 2 should bleed profusely after breaking the supernatural horror opening gross record ...