When The Americans returns Wednesday evening for its sixth and final season, the FX spy drama wastes no time in establishing the dramatic real-life backdrop for its last 10 episodes. The season premiere, “Dead Hand,” is set in October 1987, two months before an ominous “summit” that characters keep referencing—the real-life 1987 Washington Summit, where U.S. and Russian leaders Reagan and Gorbachev discussed chemical- and nuclear-weapon control. (If episode titles are any indication, the climactic meeting will take place in the season’s eighth episode, titled, you guessed it, “The Summit.”)

In “Dead Hand,” Elizabeth (Keri Russell) is sent on a covert mission to Mexico City, where she is informed of the real-life Dead Hand, the doomsday machine engineered by Russians to automatically fire its nuclear arsenal if Russian military commanders were wiped out during the Cold War. The computerized system is such a consequential secret that Elizabeth is commanded to keep the intel from husband Philip (Matthew Rhys) and given a suicide pill in the event that she is arrested. But just how frightening was this system?

When an expert on the Russian military reported the existence of the machine in 1993, The New York Times described it as a “chilling” system that “would seem to bring to life one of the darkest fears of the nuclear era—that machines could instigate a nuclear holocaust.” William E. Odom, the former head of the National Security Agency, commented that Dead Hand—if it did really exist—would be “a machine out of control.”

“Everything in our story about the actual summit, the dates, and Dead Hand are historical,” explained Joe Weisberg, the C.I.A.-officer-turned-creator of The Americans who co-wrote Wednesday’s episode, during a phone call with Vanity Fair this week. “We took some liberties with the characters, and some of the details of the espionage. I don’t want to give away too many spoilers, but you’ll see that some of the things we added happen around the super structure of the real summit and the political dynamics that are actually taking place. Dead Hand sounds like something made up for a James Bond movie—but that’s probably true of the Cold War in general. If you look at a lot of the crazy things that happened during the Cold War, the more made up they seem, the more true they are.”

“We like to point out the Martha storyline, where Philip married Martha (Alison Wright), as an example. That seems ridiculous, but the K.G.B. did have its officers marry secretaries in order to get intelligence information. The same is true of Dead Hand—that was actually a system the Russians developed. The final pieces of the system were never actually finalized, but they had a plan for it.”

Weisberg said that he and fellow executive producer Joel Fields knew that they wanted to fast-forward action to set the final season against the 1987 Summit since Season 4.

“Jumping those three years and getting to Gorbachev seemed to give us exactly what we needed both for the historical placement of the final act of the drama, but also what we needed to put Philip and Elizabeth in opposition politically, as this final season heats up.”

If reports from December 1987 are any indication, the Summit will provide a rich, suspense-packed backdrop. About 20 years ago, the Cold War meeting was so anticipated that a half-dozen law-enforcement agencies, including the K.G.B., worked together to create “the most well-secured Washington, D.C., in history,” according to a 1987 Washington Post report. The Washington Post also outlined other unprecedented security precautions taken in the pre-9/11 age: an armored limousine that was flown in for Gorbachev on a secure cargo plane; sewers swept by security teams and covered with manholes; and agents wielding Uzi submachine guns.