Australian actress Rebel Wilson doesn’t seem like the sort to get easily embarrassed – but even she managed to mess up a meeting with film star Brad Pitt.

Too nervous to speak, she just smelled his hair.

Brad Pitt's hair smells "like unicorns", according to Rebel Wilson
Brad Pitt’s hair smells “like unicorns”, according to Rebel Wilson (Jimi Celeste/AP)

Appearing on the Graham Norton Show to chat about her latest film How To Be Single, she admitted: “I was at the SAG Awards and got to meet Brad Pitt but I was too nervous to say anything so I just smelled his hair.

“It was so embarrassing.

“You’re really packed in like sardines and everywhere you turn there is someone mega famous and you don’t know what to do so you smell their hair.”

Rebel Wilson appeared on the Graham Norton Show alongside Julianne Moore, Ant and Dec and Little Mix
Rebel Wilson appeared on the Graham Norton Show alongside Julianne Moore, Ant and Dec and Little Mix (Ian West/PA)

When asked what it smells like, she recalled: “Like unicorns.”

It seems Rebel has a celebrity hair obsession – one that has also led to an awkward moment with Nicolas Cage.

The two appeared together in 2007′s Ghost Rider, when Rebel – in her less famous days – played “girl in alley”.

Nicolas Cage
Nicolas Cage (Lionel Cironneau/AP)

She told Graham Norton: “I was told, ‘What ever you do don’t look him in the eye and don’t speak to him unless you’re spoken to’. You’d think it was a myth but I was actually told that.

“I, of course, broke all the rules. He came up to me and I said ‘Wow, you look really good’ and touched his hair and realised it was a wig.

“He was really angry! That was my first Hollywood experience.”

Rebel Wilson, Alison Brie, Dakota Johnson and Leslie Mann attending the European premiere of How To Be Single
Rebel Wilson, Alison Brie, Dakota Johnson and Leslie Mann attending the European premiere of How To Be Single (Ian West/PA)

The Pitch Perfect star also revealed that agents couldn’t see her potential as an actress at first – perhaps because she did not have the typical body type to join soap opera Home and Away.

She said: “At my very first agent meeting I got rejected after they looked me up and down and said, ‘You’ll never be on Home and Away so we’re not going to take you’.

“I guess they couldn’t see me in a bikini down at Summer Bay!”

The Graham Norton Show airs tonight on BBC One at 10.35pm.