United Kingdom, June 25 -- Milly Alcock snuck her House of the Dragon co-star Fabien Frankel onto the Supergirl set, disguised as her make-up artist.

The 26-year-old actress worked on the superhero blockbuster at Leavesden Studios in Watford, England, the same building where her old show - in which she played the young Rhaenyra Targaryen - is filmed and though she didn't have time to visit the production, she managed to get the actor onto her set, but he almost ran into trouble.

She told Entertainment Weekly: "I snuck Fabien on [the Supergirl] set one day, and he almost got in trouble.

"Fabien was pretending to be Natalie, the make-up artist, because Natalie was our make-up artist on House of the Dragon.

"But Craig [Gillespie, directo...