Exciting news for Keri Russell and Matthew Rhys, co-stars of the Cold War spy drama "The Americans" — which just so happens to be the best show on television that you're not watching.

Shortly after teaming up for the show, the pair began dating. And now, according to Us Weekly, they've kicked things up a notch with their own little spy-baby on the way.

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"Keri is more than four months along," a source says. "It's so exciting for them."

The couple dodged rumors about their dating at first before stepping out together officially in April 2014. The former "Felicity" star has two children — son River, 8, and daughter Will, 4 — with ex-husband Shane Deary.

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Russell's rep didn't respond to requests for comment, though I'd imagine looking after a spy for the last few years has made them more prone to keeping secrets than usual. 

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