(CNN) The following contains spoilers about "The Americans" series finale.

"The Americans" resisted any temptation to do a "cute" finale, to somehow link this Cold War-era drama to the Russian controversies of today. The result was an understated but gripping extended episode, one that brought home the price paid by these Soviet spies hiding in plain view, while testing the bonds of loyalty and friendship.

The FX series has always seemed to come with a natural expiration date. The fall of the Berlin Wall loomed over the activities of these Reagan-era Russians, Philip (Matthew Rhys) and Elizabeth Jennings (Keri Russell), whose two children grew up unaware of their origins, before daughter Paige (Holly Taylor) was gradually brought into the family business.

Moreover, a collision appeared inevitable between the couple and their neighbor Stan Beeman (Noah Emmerich), a generally capable FBI agent who had managed to remain oblivious, until the closing flurry of episodes, to the espionage transpiring right under his nose.

Series creators Joe Weisberg and Joel Fields paid off on that promise, and then some, in a remarkable tense garage scene in which Stan confronted the trio, expressing understandable feelings of anger, hurt and betrayal. "I would have done anything for you, Philip," he said, before finally choosing to let them go.

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