Michelle Dockery spoke about Kate Middleton’s visit to the set of “Downton Abbey” during Tuesday’s “Tonight Show”.

Dockery, who plays Lady Mary Crawley on the hit British series, said of having the Duchess of Cambridge watch her rehearse: “This is probably what it felt like for a court jester back in the day performing for the royals.”

RELATED: ‘Downton Abbey’ Fans To Get The Chance To Stay At Highclere Castle

“We were quite nervous. But she was just, of course, so charming and gracious and beautiful.

“It was such a special day for everyone.”

Dockery also took part in a “How Dare You!” skit with Fallon on the show, with the pair complaining about Oreo Thins and air mattresses in a very posh manner.

RELATED: Michelle Dockery, Elizabeth McGovern Reveal Dame Maggie Smith ‘Loves A Meme’, Talk Kate Middleton ‘Downton’ Set Visit

The actress moaned, “If I had a predilection for sleeping inside of a bouncy castle, I would spend the night inside a Chuck E. Cheese. You are good at neither holding air nor being a mattress. You leave me bone-weary.”