By Owen Gleiberman
Updated August 17, 2001 at 04:00 AM EDT

The Scottish actress Tilda Swinton has the face of a perturbed-looking Victorian doll. In the past, she has used her chilly looks didactically, but in ”The Deep End,” she plays a Lake Tahoe mother who tries to cover up a murder, and Swinton seems liberated as an actress. For a while, the film lures us into a pleasurably old-fashioned web of guilt, treachery, and logistical cunning. Yet from the gruesome coincidence of the corpse’s first appearance, nothing that happens is entirely plausible.