Chiwetel Ejiofor learned to play the violin for his role in 12 Years a Slave as it's such a tricky instrument to pretend to play.
The 36-year-old actor told Hello! magazine: "It turns out the violin is a very tricky instrument if you're trying to fake it, so I got a teacher. She was great and we'd practice when we had any time – lunch breaks or whatever.
"It was good to learn the tunes and the different positions because it's a fiddling this which is also quite complicated."
His 12 Years a Slave co-star Benedict Cumberbatch often plays the violin when starring in Sherlock and Ejiofor added: "[Benedict] said he always looks like he can't play because they cut him in a strange way or they just don't let it run with the same music he's been learning, so he's always like, 'I could play that by now but it looks like I can't'."