The glowing red telephone on the president's desk is one of the most recognizable images of the Cold War, but it never existed. The real Moscow-Washington hotline was never a phone and never red. This episode traces its origins to the Cuban Missile Crisis, when a 3,000-word message from Khrushchev took nearly 12 hours to reach Kennedy through cipher clerks, Western Union telegraph lines, and bicycle messengers, and explains why the State Department and Kremlin bureaucrats initially resisted a faster link.

From the 1963 Geneva agreement onward, the episode follows the technology from exchanged teletype machines and a Norwegian one-time-pad encryption device, through a cable route that ran from Washington to London, Copenhagen, Stockholm, Helsinki, and Moscow and was cut by a Danish bulldozer and a Finnish farmer, to satellites, fax machines, ...