War veteran Horst Muller is haunted by dreams of an unspeakable day of violence that he can never forget. Did his best buddy -- now seemingly lost forever -- betray his friendship by fatally shooting unarmed POW'S ? Will he ever put aside the guilt and shame of not halting the death of a man he had seen as a kindred spirit? And what of the mysterious letter he received decades ago that he can't bring himself to open? When his computer-gaming grandson makes friends with a boy he knows only as Paul, it sets in motion a trans-Atlantic quest for the truth of what really happened that fateful day in an infamous massacre.