I always thought the events that took place on the Hill of Goats circa 1940 made up the ingredients for the greatest murder mystery never told. In 1943 the retreating German army announced almost gleefully that they had uncovered a mass grave of Polish officers numbering around 4,500 corpses. The Nazi's, ignoring their own dubious track record of atrocities, made a big deal of implicating the Russian army. It is often forgotten that 14 days after Germany invaded Poland in 1939, the Russians did likewise.

After the war Russian forensics experts identified german cartridge cases at the crime scene and shifted blame back to the Nazis.

And thus it might have rested but then somewhat unexpectedly in 1990, Mikhail Gorbachev announced that the massacre, now with a body count exceeding 22,000, was the work of the NKVD, the Russian Secret Service.

Wajda's film concentrates on a few individual officer's, a professor and their families to tell the sorry tale.