Doctor Who star Karen Gillan reveals shocking look for Guardians of the Galaxy

While director James Gunn revealed the much-discussed cast for offbeat Marvel movie 'Guardians of the Galaxy', actress Karen Gillan had a big reveal of her own planned.

Pitching up to the panel at Comic-Con in her trademark flowing ginger locks, she soon whipped off what transpired was a wig to show off her freshly shorn barnet.

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The former 'Who' star, who is playing Nebula in the movie, spoke of the radical move to rid herself of hair.

“I was a little worried that I was going to look like an overgrown foetus, but it's liberating,” she said.

Though the film is only two weeks into filming, some early footage was also shown, and the tone appears to be firmly in the irreverent camp, rather than taking the 'dark' comic book adaptation route.

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Alongside the already announced Chris Pratt, Benicio Del Toro, Michael Rooker, Zoe Saldana, Djimon Hounsou, Lee Pace and Dave Bautista is British actor Peter Serafinowicz, who appears to be playing an associate of John C. Reilly's character. Rhomann Dey.

No word yet on who is to voice what are likely to be CGI characters Groot and Rocket Raccoon (a tree and a raccoon, respectively) but the shoot in London is in its early stages.

It's due out on August 1, 2014.