While in Switzerland, Bob accidently discovers a chemistry manuscript (signed by Marco Polo) telling the location of a strange chemical in Russian Turkistan......a chemical that explores with fifty times the force of dynamite. Bob and Tim head for this location before the Nazis discover it and use it for their own ends.; The Gestapo orders von Swineman to capture Professor Foray before the French underground can move against the Nazis. During a struggle with the arch villain, the Terror takes a pailful of double-strength ammonia into his eyes and falls out of a window to the ground. When he awakens, Tim discovers that his partner is suffering from amnesia!; While in Washington preparing for a mission, the Terror spots a man attempting to get into the White House to see the President about an invisible cloak he has invented. When he doesn't have any success, the man decides to sell his creation to the Nazis, which he does. But he's doubled crossed, and, before his death, the inventor places a curse on the cloak..; The U.S. Cavalry enters the town of Twin Peaks in search of horses to buy at $30 a head, and is told that there is a large herd in the area, but the leader of the herd, named Thunderhoof, would kill any man trying to get any of the horses.