"Operation OPEC - Terror Attack in Vienna" - On December 21, 1975, six terrorists including the Germans Gabriele Tiedemann and Hans-Joachim Klein, led by Venezuelan top terrorist Carlos, attack the participants of the OPEC conference in Vienna and take eleven oil ministers and dozens of employees hostage. The action kills three people. The lavishly researched film reveals the background of the spectacular attack and establishes connections. The investigators, former hostages and some of the terrorists involved are heard..