Since joining Casualty in January, Hannah Spearritt has been causing quite a stir as troubled criminal Mercedes Christie.

The character is a far cry from the star’s squeaky clean S Club 7 days, which gave her four UK number one singles, and comes after five seasons of time-travelling action in hit TV series Primeval.

We caught up with Hannah to talk about her love of Casualty, her dramatic plot lines, and find out whether she’ll ever return to music…

How have you found working on Casualty so far? I don’t want to start with a boat load of clichés, but it really is like one big family, they were all amazing and an absolute credit to the show. Oh well, all clichéd up now… [Laughs] No, in all seriousness, it’s such a genuinely lovely group of people to work with – a bit of a dream job really!

Were you a fan of the show before joining? Yes, I used to watch it every weekend when I was a kid. It’s one of the few shows that has stood the test of time, and for good reason. For me, when I was younger, Casualty was one of the shows that epitomised great television and acting, airing in that prime Saturday slot.

What was it that drew you to the role of Mercedes? I love that she’s a little trouble maker! The prospect of doing something completely different that could potentially challenge me in many ways was really appealing, and that proved to be the case, as I’m sure you can imagine my life has been a long way removed from that of Mercedes.

You’re no stranger to the small screen – how has this project differed from previous acting roles? Probably the most obvious difference was the locations we filmed at, Casualty is pretty much all done in Cardiff at the studios whereas previously I’ve been in remote, isolated corners of the country. From an acting perspective, though, the one major difference is the number of cast and crew and the huge team atmosphere. There’s always more than one set filming at the same time.

Was there anything in particular you did to prepare for your character? Yes, I smoked crack and took ecstasy everyday, didn’t want to break character [Laughs] No, unfortunately there are limits on how much you can imitate your character’s traits. Or fortunately I should say! Actually, what I really did was I styled her character somewhat with repeated trips to Camden market where I bought all sorts of crap. It was great fun – braids, nose rings, earrings and all sorts.

How does it feel watching yourself back on TV in a role so different from yourself? It always starts with nervous excitement, I have to be prepared to cover my eyes in case I’m unbearable. It can also be quite frightening watching in HD during the close ups! Apart from that it’s great.

Mercedes is a trouble maker, but do you think there’s a good side to her? Well, yes, I think for someone not to have a good side they’d have to be clearly psychopathic, and seeing her fear for her son’s life there is a strong indication there that she cares for others. How much, or how little, I will leave up to you to decide when all has been revealed.

Can you give us a hint of what’s in store for Mercedes in future episodes? Everyone loves a trier, but you know I can’t tell you that! What I will say is that it’s endless action and drama every time she’s knocking about.

What’s the reaction been like from fans? My fans are always so supportive, they’re amazing. I do look on social media to see what people are saying as I need to be on top of things while I’m working, and I love catching up on all the gossip.

Would you ever consider a return to music, or is acting where your heart lies now? Yes, absolutely, if the opportunity presented itself again, which it just might do! I’m sure I would give it serious consideration, after all it’s so much fun. I love a little boogie…