Real-life royalty collided with fictional kings and queens, as Duchess of Cambridge Kate Middleton visited the set of “Downton Abbey” on Thursday.

Middleton, a big fan of the drama, checked out props, watched scenes as they were filmed and chatted with the stars as she toured the set. It’s hard to tell who was more excited — the cast and crew, or the duchess.

“We are so honored to have had Her Royal Highness the Duchess of Cambridge join us on the set of ‘Downton Abbey,'” said Gareth Neame, executive producer, and managing director of Carnival Films, which produces the series. “The Duchess is a great fan of the show, so it was interesting to see her step into the world-renowned sets and see the characters come to life. She was so incredibly gracious to spend time with our actors and those behind the camera who bring the saga of the Crawley family to life.”

When Middleton arrived to the set in the morning, 4-year-old twins Zac and Oliver Barker, who play Lady Mary’s son George, greeted her with an adorable welcome.

She later made her way to the hair and makeup department, meeting Phyllis Logan, who plays Mrs. Hughes. In the photos, Middleton can also be seen chatting with Michelle Dockery, who plays Lady Mary Crawley.

See photos from her day below, courtesy of Getty Images.