Emily Blunt has admitted that singing in front of her Into The Woods cast mates was like showing them her underwear.

The 31-year-old actress has revealed she was absolutely terrified at the thought of performing in front of co-stars Meryl Streep, Anna Kendrick and James Corden, but says all the cast shared her fears of doing something so ''intimate''.

Speaking to Stylist magazine Blunt said: ''My knees were knocking walking into the auditions. It's a very intimate and personal thing to sing for somebody, especially a musical god like Rob Marshall.

''It's why people have to be drunk to do karaoke.

''On the first day of rehearsals there was a hideous moment when Rob said, 'OK, we're going to sing now' and everybody just screamed. Because here it was, the moment where everybody had to suddenly show their underwear.''

Despite her nerves, Emily enjoys singing karaoke and revealed what songs she likes to sing: "'I love Janis Joplin. Sometimes if I'm coerced I'll do Aerosmith's I Don't Want To Miss A Thing. And I love Try a Little Tenderness by Otis Redding, but that's usually later on in the night.''