Irish-German actor Michael Fassbender felt "vulnerable" wearing a giant fibreglass head in his new comedy Frank.

Speaking to The Guardian, the 37-year-old 12 Years a Slave star said: "It was kind of weird in the beginning, the way it sits on your head. You feel a little bit vulnerable because you've not much peripheral vision. You can't hear that well either.

"But it's quite liberating as well, in the way that masks are. It's amazing how many emotions that face manages to convey. It can look vulnerable, it can look sinister, at times it looks confused."

Frank hits cinemas on May 9.