Here's Bloody Disgusting's plot synopsis:
So that's pretty much the video game Silent Hill 3 in a nutshell. At least they'd have something effective to work from. If the title didn't tip you off, this is planned as a 3D adaptation, which could possibly work: seeing Pyramid Head or some of those other freaks in full 3D would be neat, assuming they don't overdo the "stuff flying at the screen" motif.
The sequel follows heather Mason, along with her father, who have been on the run - always one step ahead of dangerous forces that she doesn't full understand, Now on the eve of her 18th birthday, plagued by horrific nightmares and the disappearance of her father, Heather discovers she's not who she thinks she is. The revelation leads her deeper into a demonic world that threatens to trap her in Silent Hill forever.