Between her "Doctor Who" Christmas Special cameo alongside Matt Smith and "Guardians of the Galaxy," Karen Gillan is one popular woman.

Recently, the "Doctor Who" 2013 Christmas Special titled "The Time of the Doctor" aired across the world. It was an emotional Special due to Matt Smith's final appearance as the Doctor.

But it was doubly emotional as former companion Amy Pond aka Karen Gillan also made a last-minute cameo to say goodbye to her Doctor.

"It was just nice to bring her back, also I just thought it would be good for Matt to have her on set," said executive producer Steven Moffat.

Of course, Karen Gillan dawned a wig due to her filming for "Guardians of the Galaxy," but so did Matt Smith, who shaved his iconic Doctor-ly hair for Ryan Gosling's film "How to Catch a Monster."

"They're very good wigs but they're both wigs. Though in Karen's case that's her own hair," added Moffat according to Herald Scotland.

"That wig is made of her own hair, it's just detachable now. When they cut her hair they made her a wig of her own hair. Didn't she look lovely?"

Karen Gillan certainly seemed to think so, praising the Matt Smith farewell performance on "Doctor Who" on Twitter.

A job well done Mr Smith.

— Karen Gillan (@KarenGillan2) December 25, 2013

But Whovians needn't worry, as Karen Gillan will soon be back in "Guardians of the Galaxy" as the villainess named Nebula.

"Karen Gillan says her 'Guardians of the Galaxy' villain is a bald sadist with bionic limbs and an American accent," reported RedCarpetNewsTV.

"The one I played was so strong and evil and sadistic and amazing. I can't give too much away, but she's pretty creepy," said Gillan according to CosmicBookNews.

And at San Diego Comic-Con over the summer, fans got a brief glimpse of Karen Gillan as Nebula, and you can check out the screenshot above.