'The Americans'

KGB spies Elizabeth Jennings (Keri Russell) and Philip Jennings (Matthew Rhys) try to determine if a Navy SEAL (Lee Tergesen) killed their comrades on "The Americans." (Craig Blankenhorn / FX)

Posing as CIA officers, Soviet spies Elizabeth Jennings (Keri Russell) and Philip Jennings (Matthew Rhys) confront a dangerous SEAL suspected of murdering their comrades on “Behind the Red Door,” Episode 6 of “The Americans” on FX.

Because of his homosexuality, Navy Capt. Andrew Larrick (Lee Tergesen) was blackmailed into working for the Soviets. Now his two KGB contacts and their daughter are dead, but Larrick denies pulling the trigger.

“I didn’t kill them,” he says. “I wanted to. Someone got to the bastards before I did.”

With a gun strapped to her thigh, Elizabeth is ready to shoot Larrick. But she holds her fire after discovering the SEAL is working on a mission that could affect the USSR and its allies.

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That black op involves training Nicaraguan rebel commanders at a secret location in America.

Seeing Larrick as a threat to their family, Elizabeth and Philip request Moscow’s permission to kill him. But Kate (Wrenn Schmidt), their new KGB handler, has other orders.

She tasks the spies with assassinating the rebels and exposing the training camp to the public.

“The American people deserve to know what their government’s doing behind their back,” Kate emphasizes. “You’ll need Larrick.”

To work closely with the SEAL, Elizabeth and Philip realize they must reveal their true identities. And that puts their lives in greater peril.

So if Larrick didn’t murder the KGB agents, who did?

Claudia (Margo Martindale), Elizabeth and Philip’s former handler, nervously admits she had a relationship with a man and told him too much about her covert activities.

“I trusted him,” Claudia confesses to Elizabeth. And that trust may have compromised the safety of her agents.

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Claudia also appears worried about her own safety as she bids goodbye to Elizabeth with an air of finality.

To obtain documents about the training camp, Elizabeth requires access to the private office of a U.S. congressman. That’s why she enlists the help of Lucia (Aimee Carrero), a Nicaraguan intelligence officer masquerading as a grad student.

Lucia’s “boyfriend” is Carl (Nick Bailey), a narcotics-abusing congressional aide. Declaring she wants to have sex in the politician’s empty office, Lucia coaxes Carl into unlocking the door.

This gives Elizabeth an opportunity to sneak inside and photograph confidential files.

Now that she has the intel, Elizabeth urges Lucia to break off her relationship with Carl before a government investigation leads back to her.

“I don’t need so many lessons,” Lucia insists testily. “I can do my job.”