Throughout the film, Julia Roberts wears enormous ball gowns. On the set, her children hid underneath her skirt without anyone knowing. In between takes, Roberts had her children removed from the set because she was concerned about them hearing her "vile" dialogue as the Evil Queen.
Almost all of the unlikely seeming beauty treatments the Queen undergoes are actually real treatments you can get at spas all over the world. Among the real ones are: the bird poop paste, the chocolate (or clay, it's not clear which it is since it's brown) mask, the snake massage, the snail slime, the maggots and the tiny fishes that eat away dead skin cells. One of the few (if not the only) fake treatments shown is the bee sting to the lips to plump them up, although lip plumpers really do contain (usually botanical or chemical, not insectoid) irritants.
The original script included a scene between a shirtless Prince (Armie Hammer) and the Queen (Julia Roberts) in which the Queen remarks how smooth his chest is. This line had to be altered when Hammer refused to shave the hair off his chest for the scene.
According to Julia Roberts, Mirror Mirror is the first film that made her young children aware that their mother was a famous film actress. Even though her children showed a large amount of enthusiasm about the Evil Queen, Roberts did not let them see the film for they were "too young." In fact, Roberts kept her work a secret from her children while Mirror Mirror was filming. "They're too young for it (the movie) and I think they would find it (me) disturbing," she said.
Until the filming was complete, Mirror Mirror was known as The Untitled Snow White Project. Though director Tarsem Singh's intention was to make a family-friendly action comedy, he admitted to the press that he was disappointed with the title Mirror, Mirror. He said in an interview that we would have preferred the simple title of "Snow."
According to Julia Roberts, her costumes in the film were both heavy and almost impossible to move in. At one point while shooting, Roberts turned rather quickly to her co-star Nathan Lane during a take, and pulled a muscle. Needless to say, they had to stop shooting. Lane asked if Roberts was all right, and she responded with, "I think I just ripped something."
The peacocks painted on the wall in the Queen's room are direct copies of the ones painted by James Abbott McNeill Whistler in his famous peacock room (1876-77). The glass tables were designed by famous art nouveau jeweler and artist Rene Lalique.
Julia Roberts said in an interview, "I was like, 'this is a terrible idea.' I was against it (the movie) a thousand percent." However, when Roberts had a meeting with director Tarsem Singh, her opinions changed completely. "I am such a fan of Tarsem, and fell under his spell."
Lily Collins auditioned for Snow White in Snow White and The Huntsman (2012), but lost to Kristen Stewart. Sam Claflin auditioned for the Prince, but lost the role and later went on to be cast as the prince in Snow White and The Huntsman. Coincidentally, Collins and Claflin later starred together in Love, Rosie (2014).
At one point during the chess game at the beginning of the film, the Queen says "loose lips sink ships" to Brighton. When the aid asks which ship is to be sunk, the Queen says that is just an expression. Actually, the phrase was coined in Britain during World War II regarding the secrecy of route of Atlantic convoys. Since Germany had spies everywhere, an indiscretion could, quite literally, sink a ship.
The trivia items below may give away important plot points.
In many traditions of Snow White, the actress playing the Evil Queen also plays the Witch/Crone role with the poisoned apple. Producers kept videos and photographs of Julia Roberts's "hag" transformation under wraps before the film was released to both surprise and lure audiences. However, director Tarsem Singh revealed in an interview, "Julia does become a hag in the end, it's pretty gross."
This is the first adaptation of The Brothers Grimm: Snow White where both the characters - Snow White (Lily Collins) and the Evil Queen (Julia Roberts) - have a romantic relationship with the Prince (Armie Hammer).