Scarlett Johansson had just two days to master the Russian language for her role in The Avengers movie.
The Hollywood actress reprises her Iron Man 2 character Natasha Romanoff, aka Black Widow, in the blockbuster, and got to grips with her superhero's native tongue for some key scenes.
However, Johansson soon realised she had just 48 hours to work with a dialect coach to learn some tricky Russian speeches.
She tells Reuters, "I had two days, so I had to learn it phonetically. I knew what I was saying but I had to be able to pronounce it and breathe some life into the lines so that it didn't sound like I was repeating some Berlitz (language learning) tape.
"We hired this great Russian translator, and she worked with the dialogue coach. She was really expressive, which helped, so my mouth found the words in a way that didn't just sound like I was a parrot."