First lightning -- Venona -- They built a wall -- Spy training: Venona-style codes -- Spy training: rocket launch -- Spies -- The Cambridge spies -- Clever girl -- Spy disaster -- The scholar spy -- Grandma was a spy -- The spy who skied -- The magician spy -- Animal agents -- Spy training: ski team race -- Spy training: parachute men -- Special missions -- Tunnels to freedom -- Operation Blue Peacock -- Last train to freedom -- Project Iceworm -- The race for space -- Operation Ivy Bells -- The Canadian caper -- Girrmann escape group -- Spy training: carrot submarine -- Spy training: glaciers move -- Secret weapons -- Gadgets and gizmos -- Spy in the sky -- Take shelter -- The thing -- Space needles -- UFOs -- Spy training: flying saucer 101 -- Spy training: your own UFO.