If you haven't seen it already, click here to read the first part of our interview with Karen, which focuses on all things Cesca and Jonah.
Away from Waterloo Road, however, Karen has already appeared in films The Colour of Magic, Scorpion King 2 and Flight of Fury, while she currently has more acting roles and an intriguing new music project in the pipeline.
Here, in part two of the interview, Karen chats more about Waterloo Road and what she has in store for the future.
Along with Lucien, who plays Jonah, is there anyone else who you particularly enjoyed working with at Waterloo Road?
"Oh, I'm so spoiled for choice here because I've loved working with all of them. In episode six, I had so much fun working with Darcy Isa and Holly Kenny, doing the drugs storyline. Amanda Burton is amazing to work opposite - she's such a well-respected actor and I loved her work on Silent Witness. A lot of my early scenes were with her and it was great to work with someone who is so seasoned and so amazing. And I absolutely adore Philip Martin Brown - he's so much fun to work with and we're dear friends. But the whole cast and crew were great to work with - it was a great family to be a part of."
"Well, I think that Waterloo Road fans are some of the nicest fans that I've ever met or had the chance to engage with. They're so incredibly supportive and I think that's a reflection of the show and the people who are in it, because the whole team is so lovely. It was probably one of the nicest and most down-to-earth cast and crews that I've ever worked with. And the fans are exactly the same way - there's so much love and support for every single character on the show, and they also support things that we do outside of the show. I'm grateful for that, because at the end of the day, it's your fanbase who are there for you and give you the strength to carry on with the crazy journey that we're on. They're like a cheering squad, and what an amazing cheering squad to have!"
As you joined Waterloo Road in series six, how did you find the experience of joining an established show with an established cast?
"I was so excited! I'd just done The Colour of Magic and Scorpion King 2, and all of a sudden Hollywood was calling and doors for me were opening over there. But I felt that I'd skipped a really essential part that I'd so wanted to do, which is prime-time British television. So when Waterloo Road came up, I just thought that Cesca was a gift of a role and I'd be mad not to do it. I have so much love for the show and it was just great to be part of such a great cast, crew and team of people at the BBC. The show has opened a lot of doors for me and I couldn't ask for a better show to break through with on British TV."
"I've been in LA and it's been difficult to be away from home, but I've been busy in the studio writing for my new concept called The Girl In The Pink Glasses. The project is very much about marrying my love for acting with my love for music, without it being theatrical. It's celebrating that awkward teenage stage that I went through - I had a horrific acne problem and I hid behind my hair, stared at the floor and wore these ridiculous pink speckled rim glasses, and I was the mysterious freak because I never talked about what I wanted to do with my childhood dreams.
"So I've taken all of those kinds of things and put it into The Girl In The Pink Glasses. She's under the disguise of a '60s agent, like in the movies you see with Grace Kelly and Ava Gardner. So it's the trenchcoat, the fishnets, the wig and the pink glasses. And the music is pop-rock - sort of Blondie meets Gorillaz with a bit of '60s elevator music thrown in! I'm really excited about it - I've been working so hard in LA and I now have an album's worth of material. I've been asking fans to get involved by helping me to choose what my next single should be."
Do you have a preference between music and acting, or do you enjoy both equally?
"I've always wanted to do both, ever since I was a little girl. I have a sister who's ten years older than me, so when she was babysitting me, I had to listen to the music she did and watch the TV shows that she did. So, for a 4-year-old, I thought I was pretty cool because I was listening to Duran Duran and Spandau Ballet! One day we sat down and we watched Xanadu together, and I fell in love with all things Olivia Newton-John. It was from that moment that I was so bitten and I just had to act in TV and films like her, and I had to sing and make records like her!
"So that's where it all started, and I made sure that I studied diligently with my music and my acting. I made sure that I paid my dues on both and slaved away for both of them! It's really nice that new fans are now getting to know me, Googling me and picking up on tracks that I released years ago when I was with BMG. I'm really excited to be doing both music and acting - I think they feed me both creatively and I think I'm a better songwriter because of my acting, because I love telling stories in my music. Because of the lyrics, I think the music has a real heartbeat and I think that comes from being an actor."
We've also heard that you're about to do some acting with Robert De Niro…
"Yes, I am! I have a cameo in the next Robert De Niro film called Red Lights. I play Donna, who's an investigative journalist. It's only a few scenes, but my scenes are with him and I'd be mad not to take the chance and the opportunity to learn from the best again. You've got to start somewhere when you're starting to do these bigger movies, and I just feel really lucky to have the opportunity to learn from people like Robert De Niro! I hope it will lead to many more."
What would be a dream role for you?
"As an actor, you always want to play a role that is so far from you, like Charlise Theron in Monster, or Halle Berry in Monster's Ball. Something like that, which stretches you into a complete opposite, would just be so exciting and wonderfully scary at the same time because you know you've got your work cut out for you."
What other projects are you working on at the moment?
"I'm also currently on Pixelface, which is a comedy series on CBBC. It's for the big kids as well and it's produced by Graham Norton's So Television. It's about these six video game characters who live inside a games console and how they moan about each other and their human game controller. It's so funny, crazy funny! I play Alexia who's a really posh archaeologist and mummy slayer. It's a lot of fun and I think that fans who love Red Dwarf will love it. It's on CBBC at 5.45pm on Wednesdays and then on Saturdays, so I've warned all the fans that they're going to have to put up with my face on TV three times a week!
"But it's nice for them to see me play something completely different at 5.45pm on Wednesday night, and then a couple of hours later as Cesca on Waterloo Road. As for what's next, I've got the De Niro project and then who knows? Let's see where this crazy journey takes me! It pays the bills, it's a lovely day job to have and I'm very thankful for all of the support that I have from all of the Waterloo Road fans because they've been super."
Click here to follow Karen on Twitter and click here to listen to samples from The Girl In The Pink Glasses on Karen's Facebook page.
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