• LIMELIGHT: Karen Gillan, who took a course at Telford College, stars next to the new Doctor as his companion, Amy Pond
From her home in Inverness to the furthest reaches of the Space Time Vortex . . . via Telford College, the past four years have been a roller coaster ride for the 22-year-old, who stars in Doctor Who story The Eleventh Hour, alongside new Doctor, Matt Smith, on BBC1 tonight.
That journey began when Karen moved from her hometown in the Highlands to study acting at Telford College on West Granton Road in the city. It was there she met the man who would become her mentor, tutor Scott Johnston.
"I always wanted to act, but knew I had to work at it and get better, which is why I moved to Edinburgh," the flame-haired actress recalls. "It was at Telford that I realised I could pursue it as a career."
Karen did Telford's one-year HNC Acting and Performance Course, a period she now describes as "such an important year".
"That was when I first worked with my tutor, Scott Johnston. In terms of my career, he has been such an influence on my life. It was he who encouraged me to carry on – he believed in me."
She explains: "He was so passionate about his job that he really got to know each of his students so that he could then pick roles for us that challenged us as actors. I've never met such a passionate teacher in all my life and I can't express how much I learned on that course. We're still in touch now, we have become really good friends, and he's always phoning up to see how I'm doing."
Since the announcement of Karen's casting in Doctor Who, it's been fairly easy to keep up with "how she's doing", although for a while the actress had to remain tight-lipped about her good fortune.
"I found out I'd got the part on the day of my second audition with Matt, so at least I didn't have a really long wait. It just didn't feel real, and I couldn't believe it . . . but I wasn't allowed to tell anyone about it. They even had a codename for the role because it was so top secret – Panic Moon, an anagram of companion."
Even after Karen was cast, the veil of secrecy wasn't lifted. "I wasn't allowed to tell anyone, but my boyfriend was with me when I found out so there was rather a lot of screaming," she laughs.
One person Karen couldn't wait to tell was her mother – a long-time fan of the show with a Dalek bubble-bath to prove it.
"My mum is ecstatic," she laughs, adding: "Getting this role is like getting no other because before you've even played it, you have a huge fanbase. It's like walking into an already established role. Instead of that fanbase developing, it's instant. That was a bit daunting even though I was already aware of the iconic nature of the programme because my mum is a huge fan of the show."
Karen reveals that she decided not to tell her parents about the role right away, so as not to spoil the surprise.
"When I finally did tell them I made a special day of it and my mum took a day off work. She just couldn't believe it when I told her. She was doing the dishes and she literally stopped in her tracks and cried."
Playing Amy Pond, however, isn't Karen's first Doctor Who role. In the 2008 episode The Fires Of Pompeii, she played a soothsayer, opposite David Tennant and Catherine Tate.
"That was a really small role, but a nice introduction, although it wasn't a case of the production team seeing me play a soothsayer and thinking, 'Oh she could be a companion.'
"There's a whole new production team in place for this series. I just auditioned and, luckily, wasn't recognised, probably because as the soothsayer I was so obscured by the make-up."
While careful not to give too much away about her forthcoming adventures, Karen does admit that one highlight so far was stepping into the new-look Tardis for the first time.
"That is when you know that you are in Doctor Who. It was really cool," she says. "I was in awe of the whole thing. I'd seen the old one so much on TV and then I walked into the new one and it was breathtaking; just the sheer scale of it. It was so exciting. I thought to myself that I had to remember that moment for when Amy walked into it for the first time."
The other highlight, naturally, was working with her co-star, Matt Smith, at 27, the youngest actor to have played the Time Lord. Series producer and writer Steven Moffat described him as managing "to be old and young at the same time". Karen agrees.
"That's the great thing about the Doctor, he has the energy and mischief of a young child as well as the wisdom, age and intelligence of someone a lot older," she says. With Matt's performance, he's so believable that he isn't human. He has all these things that he does that make you believe he is an alien and you're drawn in by that."
It's the relationship between the Doctor and his companion, however, that lies at the heart and soul of the show, believes Karen.
"We've had a blast filming because we are both going through the same journey, at the same time.
"I'm not walking into the show with the Doctor already there. That's quite nice.
"With (producer] Steven Moffat's influence, the fairytale and magic of the show is fairly prominent in the new series and the dynamic between Amy and the Doctor is a really interesting one," reveals Karen. "Amy is this alpha female and, of course, the Doctor is the ultimate alpha male, so when they meet they combust, but Amy can really hold her own against him and Steven's written some great one-liners."
That said, just like the Doctors, companions come and go, so will Amy Pond be around for the foreseeable future?
"It's all up in the air in the moment," is Karen's candid response, "but I certainly wouldn't say no. We'll just have to wait and see."
Doctor Who, BBC1, 6.20pm