This is a documentary, going into a specific plot to kill Hitler. A group of experts try to recreate the events, and test two variations on it, to see how close the people actually came to succeeding. It consists of the experiment, old footage from the period and recreations. They give some basic background to the attempt, and there's plenty of info about it, the room, the placement of the target, etc. They also show the actual explosions that they cause(all in the interest of historical exploration, of course).