Matthew Rhys

Disguised as a janitor, KGB spy Philip Jennings (Matthew Rhys) steals secrets from a computer lab on "The Americans." (Craig Blankenhorn / FX)

Stealing secrets about an Internet prototype requires KGB spy Philip Jennings (Matthew Rhys) to work with an alcoholic Soviet sympathizer in Episode 7 (“Arpanet”) of “The Americans” on FX.

A visit to the apartment of Charles Duluth (Reg Rogers) confirms Philip’s suspicions. Charles is an unreliable drunk.

He’s sober during a meeting with a tech expert, however, who explains in layman’s terms how a “virtual highway” connects military and scientific communities worldwide.

“It’s sort of like God,” Professor Rosenbloom (Geoffrey Cantor) says of the Arpanet, “except without the big beard and flowing white robes.”

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For Philip to download classified data, he needs the entry code for a computer lab. But Charles nearly bungles his job of obtaining the code. And Philip, disguised as a janitor, reluctantly kills a researcher who arrives unexpectedly.

“I’ll be better next time,” promises Charles, swearing he’s given up alcohol. But that cranberry juice he's drinking is mixed with vodka.

Philip’s KGB wife Elizabeth (Keri Russell) also works with a difficult partner. She’s Lucia (Aimee Carrero), a Sandinista intelligence officer determined to avenge the deaths of her Nicaraguan countrymen.

Lucia’s assignment -- assisted by traitorous SEAL Capt. Andrew Larrick (Lee Tergesen) -- is to infiltrate a base where the U.S. military will train two Contra field commanders.

Then Lucia is to deactivate an electric fence so Philip and Elizabeth can sneak into the camp and assassinate the rebels.

Impetuous Lucia has her own agenda, however. Even though the naval officer is an invaluable asset for the Soviets, Lucia wants to kill him for helping Contras attack Nicaragua’s government.

“Larrick is a monster,” Lucia declares. “He has to pay.”

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“Larrick is a monster but he’s our monster,” Elizabeth counters, emphasizing that whatever atrocities he’s committed are nothing compared with “what he can and will do for our cause.”

At the Soviet Embassy in Washington, KGB double agent Nina Sergeevna (Annet Mahendru) reports a dangerous request from her lover, FBI Agent Stan Beeman (Noah Emmerich).

Stan wants Nina to undergo a lie-detector test and thereby prove she’s not spying for the USSR. But she is spying, of course.

“If I fail the test, he’ll kill me,” Nina exclaims to her superiors, Arkady Ivanovich (Lev Gorn) and Oleg Igorevich (Costa Ronin). Oleg tries to calm Nina by coaching her on how to fool a polygraph machine.

“Inside, you must be still,” Oleg says. And squeezing your sphincter muscles also works.

When Nina agrees to the polygraph test, Stan is surprised. Why the change of heart?

“Nothing changed,” Nina says with a straight face. “I love you. And if you don’t know it by now, more is the pity.”