Since it already premiered on PBS as part of “Masterpiece Contemporary” on October 25 (and on British TV in May), the theatrical release of Endgame, about the covert negotiations in the ’80s that helped bring down apartheid, is puzzling. (Did someone think this would be an instructive prelude to Clint Eastwood’s upcoming Invictus?) Michael Young (Jonny Lee Miller), public affairs director for a British gold-mining firm, secretly assembles talks between ANC representatives led by Thabo Mbeki (Chiwetel Ejiofor) and powerful Afrikaners like philosophy prof Will Esterhuyse (William Hurt); meanwhile, Niel Barnard (Mark Strong), South Africa’s reptilian head of intelligence, starts his own clandestine chats with Nelson Mandela (Clarke Peters), in the hopes of dividing and conquering ANC leadership. Written by U.K.-TV vet Paula Milne, Endgame has its share of grandstanding dialogue (“I cannot stand by and do nothing while my country is reduced to ashes,” booms Hurt) and a maddening tendency toward meth’d-out camerawork. But the principals, especially Ejiofor, rise above the starchiness that often hampers portrayals of recent, monumental history.