After a strong start, the debut feature from veteran stuntman Peter `Drago' Tiemann devolves into a disappointingly ordinary, gory monster-in-the-woods movie, with a baggy rubber suit and cops whose crime-scene investigation techniques haven't improved much since 1957's Plan 9 From Outer Space.
The setting is the Washington state wilderness, plagued by disappearances and sasquatch lore. In 1997, a boy and his grandfather vanish during a hunting expedition; viewers behold that right before an attack by clawed humanoids, the pair found the mirage-like presence of a pristine staircase, anomalously arising out of the loam.
Two decades later a woodsy expedition of adults—better written than the cheerleaders and jocks of 1980s teen-slasher films, but not by very much—explore those same woods during a long hike to their cabin. A nice build-up has the ensemble discovering bigfoot "nests" and macabre apparitions—some of which only a few of the characters seem able to see. Of course, the uncanny stairs reappear.
The baddies are a lamprey-headed race of monsters (though only one is shown) nicknamed "grub daddies," apparently from another dimension, and the ensuing low-budget fight for survival includes the retro detail that [spoiler alert] the token-ish smart, sensible black character is reserved as last to die whilst white folks escape.
Technical credits are sharp, and lurking in the horror cliches might just possibly be an anti-hunting eco-message of some sort, equating the ravenous grub daddies to the deer-shooting grand-dad. But really, the only thing certain here are a few moments of Phantasm-memorable nightmare imagery and suspicion that if the filmmakers have any logical explanations for the storyline, such facts are held in escrow for Stairs 2, Stairs 3: Grub Daddy's Revenge, Stairs 4: Too Stairs Too Furious, etc. Optional.