They are first encountered in the sewers of Silent Hill, appearing near the end of Harry Mason's journey through the town. They are also present at the Lakeside Amusement Park and in certain sections of Nowhere.
They are the ghostly form of the Grey Children; small, child-like, knife-wielding monsters, the sole difference being that Stalkers are "invisible" (vaguely delineated, and as such, hard to see).
Stalkers' danger lies in their ability to remain unseen and attack Harry in groups and to also dupe Harry into thinking they are actually Larval Stalkers. They can be subdued with gunfire from the handgun; however, they can also be defeated quite easily with either the hammer or the axe if the time is taken. If Harry is cornered, it is best to use the shotgun to finish them before they can inflict serious damage.
Stalkers are essentially the dangerous form of Larval Stalkers, which represented how "invisible" and neglected Alessa Gillespie felt in school due to the cruel treatment from her peers. While Larval Stalkers are shy and seclusive, Stalkers pose a real threat and could be symbolic of Alessa's anger emerging and becoming known.
- Although Grey Children themselves were replaced in the PAL version of the game by Mumblers, Stalkers can still be found in Nowhere.