The Tragedy of W (2010)

Snow blankets the lake at Lake Yamanaka. At the chairman of Watsuji Seiyaku, a major Japanese pharmaceutical company, a shocking event occurs. Mako, beloved by her entire family, confesses to killing her granduncle, Yohei. Following the murder, the assembled family members begin a coordinated effort to conceal the crime, staging events to make it appear as though an outsider committed the act.