Joely Richardson has defended her new film, which says that Shakespeare was not the author of the famous plays.
Anonymous, directed by Roland Emmerich, has sparked huge controversy for its contention that Shakespeare was a simpleton, a fraud and perhaps a murderer who never wrote a word of the great plays.
Joely, who plays a young Queen Elizabeth in the movie, said: "I don't see why people are threatened. At the end of the day, it's all celebrating Shakespeare."
She said the cast would sit and discuss the authorship debate during filming, and that many were swayed by various points of the film director's argument.
The film's main contention is that the actual author was the Earl of Oxford, Edward de Vere.
"All of us started to get pretty convinced, not necessarily that it was Oxford, but that it's definitely up for debate. There are just so many missing links," Joely said.
Shakespearean actor Mark Rylance, who plays an actor in the film, added: "This anger about the film is bizarre, because Shakespeare has always been a mystery.
"It's not like Emmerich is the first person to question this."
Rhys Ifans, who plays de Vere, said the authorship debate wasn't the central point of the film.
"It's a political thriller. It's a historical piece, a visual banquet," he said.