Three siblings who, after being stranded in a boat on a country river, are stalked by a faceless killer.

In his acclaimed 2018 short film “In Sound, We Live Forever”, writer-director Joshua Giuliano shrewdly split the sound and image of a slasher scenario, so that the violence was heard before its consequences were observed. This eerie dissonance laid bare an insidious undertow inherent to the horror genre, a current that, once one is caught up in it, carries its victims toward a seemingly grisly inevitability from which there is no escape. Such is the current that three siblings find themselves adrift upon in “River”, Giuliano’s audacious nerve-shredder of a feature debut.

Having convened to scatter the ashes of their late father from a family motorboat, embittered sisters and their younger brother stall out beneath a derelict bridge along a rural waterway. Familial wounds are provoked, and fingers are pointed, first at each other, but soon at the sudden appearance of a strange man eerily staring from the shoreline. Tall and statuesque, the figure’s face is seemingly without features or emotion, just a palpable, anonymous malevolence. And when he stops merely staring, the family must come together and start surviving.

“River” premiered at the Toronto International Film Festival.