It’s Valentine’s Day in the state of Victoria, Australia in the year 1900. A group from a local girls’ school goes on an excursion to the foot of an eerie, vast geological formation called Hanging Rock. Three girls and one schoolteacher climb up to explore it. All but one are never seen again. This summary constitutes the essential plot but only the first act of Peter Weir’s 1975 film, based on the novel by Joan Lindsay. The remaining two acts concern the surviving characters’ struggle to make sense of what happened on the rock. Yet, sense is not what the film intends to deliver. Rather, it’s an anti-mystery that dismantles the nature of the mystery story itself—its love of solutions, its neat settling of the uncertainties that crime or menace introduce. What happens, this film asks, when an event resists the imposition of order, stands beyond the reach of logic or even language? Wes & Erin discuss “Picnic at Hanging Rock.”