Set seventeen years after the events of the first game, Silent Hill 3 revolves around Heather, daughter of Harry Mason. A private detective called Douglas Cartland has been hired by the cult that resurrected Samael in the first game to track her down. Under a new leader, Claudia, they want to continue the ritual thwarted by Harry in Silent Hill 1. This is because Heather, once called Cheryl, is actually Alessa, the demon’s former host. In order to bear a god for a second time, Heather’s heart must be full of hatred. The game is a series of events designed to by the cult to achieve this, the most brutal of which is the murder of Harry. But, in the tradition of her old man, she scuppers the cult’s plans and the demon is not reborn. She leaves Silent Hill with Douglas, choosing not to live in fear any longer, and takes back her old name, Cheryl Mason.
What it all means
This is actually the most straightforward story in the Silent Hill saga, and that was intentional. The developers wanted to create something completely different to the bleak, slow-paced and psychological nature of Silent Hill 2. The biggest mystery, however, is Valtiel. This faceless, disfigured monster stalks Heather as she shifts between the real world and The Otherside. His concern isn’t with Heather herself, rather the remnants of Samael within her. He’s a watchman for the cult, ensuring the god is reborn and not damaged. This is why you see him drag her body away whenever you die in the game. The monsters don’t relate in any specific way to Heather, but some of the areas she explores do - for example, the Lakeside Amusement Park where her father previously found himself in the first Silent Hill.
Normal: The god is reborn, but Heather defeats it. She leaves with Douglas.
Possessed: Heather is consumed by the god and murders Douglas.