United Kingdom, Oct. 13 -- Keri Russell and Matthew Rhys had sex while wearing their spy disguises on the set of The Americans.

The pair fell in love and struck up a real life relationship while they were playing two Soviet KGB intelligence officers posing as an American husband-and-wife in the hit TV show - and Keri has now revealed the pair had some very saucy moments on set while they were kitted out in their costumes.

During an appearance on the Dear Chelsea podcast, Keri confessed: "We were falling in love and staying up all night and having sex all the time and just wearing disguises, like, I'm f******[in] crazy wigs and wearing pearls.

"When have you ever worn pearls and [been] f****** in trailers and f****** everywhere. I mean,...