Bruce Willis proved he has a sense of humour by dressing up as Zac Efron and Sarah Palin on the David Letterman show.

The Die Hard actor adorned a basketball shirt and wig in a bid to convince the audience he was Zac Efron's big brother 'Benny Bolt' in High School Musical 3.

He later swapped his sports shirt for a pair of specs and a beehive wig to parody the Governor of Alaska.

We're not used to seeing Bruce with hair...

See Bruce playing his most unusual roles to date below