Amy Pond debuted in last year's premiere 'The Eleventh Hour', when The Doctor (Matt Smith) discovered that her bedroom contained a crack in the fabric of time and space which had erased her parents and many others from existence.
In the series five finale Amy's parents were restored to the universe and now Gillan has revealed that The Doctor's companion must face up to her difficult past.
"Well, with the last series, what I wanted to do with Amy is keep her really guarded," she told SFX. "She doesn't like to show her emotions, because she wants to seem strong and she doesn't like to be seen as vulnerable in any way, because of what happened to her in her childhood, so I kept her like that."
Gillan continued: "In this series, cracks are starting to form in that feisty exterior, and we're starting to get glimpses into other aspects of her. And having her parents back in her life definitely does have an effect on her. But it's kind of a mixed effect."
Asked about the highlights of the six episodes to air this spring, Gillan professed that a trio of particularly memorable moments stand out.
"The pirate ship [from 'The Curse of the Black Spot'] was amazing! And it was really cool going to Utah... that, for me, I think, is the favourite story we've shot so far," she declared. "Also, we get to see a bit more of the Tardis than we've ever seen."
Doctor Who returns this Saturday on BBC One in the UK and on BBC America in the US.
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