Karen Gillan ‘unlocks’ the secret of her post-Dr Who career at Comic-Con

Actor Karen Gillan speaks onstage at Marvel Studios "Guardians of the Galaxy" during Comic-Con International 2013 (Getty)

Karen Gillan pulled off a surprise (and a wig) as she revealed a shaved head at the Comic-Con event in California.

The former Doctor Who star’s crop was for a role in the Marvel film Guardians Of The Galaxy. Cutting it all off has become a rite of passage for a number of actresses: see Natalie Portman in V for Vendetta and Demi Moore in GI Jane. Pop star Jessie J recently shaved her head to raise money for Comic Relief.

For the stars, it’s a chance to declare that they are more than just a pretty head of hair (while simultaneously highlighting their fine bone structure).

But if the film offers dry up, they are left hoping it isn’t a case of, ahem, “hair today, gone tomorrow”.