(CNN) The following contains spoilers about "The Americans" Season 5 finale.

"The Americans" has capped a fifth season that couldn't match the depressing heights of the fourth -- with the twin fates of those damsels in distress Martha and Nina -- yet which has ably set up this engrossing drama's final mission.

With Russian hacking commanding real-world headlines, FX's Reagan-era drama set during the height of Cold War hostilities -- with two KGB moles hiding in plain sight -- took on somewhat different hues. The season's major thrust, however, dealt with the growing disenchantment of one of those spies, as well as the corruption of a Soviet system essentially rotting from within, paving the way for its fall along with the Berlin Wall in 1989.

Those seismic events are still a few years away from where "The Americans" is in its narrative life, but the signs are there. In fact, this season's most fascinating arc involved Oleg Burov (the terrific Costa Ronin), the former KGB agent and former embassy operative whose return to Russia unearthed his parents' unsettling past and exposed him to risk from suspicious officials.

Closer to home, Philip (Matthew Rhys) came to suspect the Soviets of various atrocities, including the use of a biological agent that he had worked to retrieve. A scheme that ultimately resulted in a teenage boy's attempted suicide further soured his outlook.

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