Hollyoaks fans get a horrifying glimpse of what Sienna Blake is capable of next week as she starts a fire at The Dog in the Pond.
When Sienna spots that Nancy Osborne (Jessica Fox) has passed out upstairs at the pub, she seizes the opportunity to expose the new mum's painkiller addiction, regardless of the danger involved.
Digital Spy recently caught up with Anna Passey, who plays Sienna, to hear more about the storyline and why this is only the beginning of her character's games.
It's hard to believe you've been on our screens for seven months already! How are you finding it at Hollyoaks?
"I'm absolutely loving it and I never want to leave! I can't believe it's been seven months already, as it's really flown by. It's great to have been so busy, so I'm really enjoying it."
How do you feel about playing such a complex character?
"It really is a dream - I feel like I've been given a gift of a part. Sienna is a bit of a villain, so she's quite exciting to play in that respect. I always think that the baddies are really fun roles to have. At the same time, I also think this is much more complicated than your standard, black and white 'baddie story'.
"Because the character is so complex, it's really exciting for me and whenever I get a new script, I'm always racing to the end of it to see what happens! I genuinely never know what Sienna is going to do next."
Did you always know that Sienna had these issues?
"When I first joined the show, the producers were very thorough with me when they explained the background of Sienna's character. I knew all about her upbringing and the problems she'd had with her family. But at that point, I didn't know the specifics and just how far Sienna would go in this storyline!"
Did Sienna start out genuinely wanting to be a friend to the Osbornes?
"I think Sienna's intentions have definitely changed as time has gone on. To begin with, Sienna really was just looking for a friend. She's had quite an unusual upbringing, because she's never really had any friends. Normally, most people learn how to socialise and form relationships with people as they grow up, but Sienna has missed out on all of that. She's only ever really had her father.
"To start with, Sienna didn't quite understand how the Osbornes worked. They're very different to her own family, but she was quite intrigued by them. I think Sienna genuinely started out wanting to be a really good friend to the whole family, but as time goes on and she sees that Nancy isn't appreciating what she has, that's when Sienna starts to turn against her. Sienna thinks Nancy is absolutely bonkers for not realising what she has."
How does the fire storyline at The Dog come about?
"Sienna is aware that Nancy has been having a problem with painkillers for quite a while. She's tried to be a friend to Nancy and support her, but her main concern is the baby. Sienna has grown up with a bad mother in her opinion, so she's worried that Oscar is now in the same situation.
"Sienna has been trying to support Nancy and guide her back towards being a good mum, but when she realises that Nancy is ignoring all of this and is still taking the painkillers, she's really quite angry about it. She wants to teach Nancy a lesson, and also open Darren's eyes about the sort of woman he's married to.
"Sienna comes in one time and sees that Nancy has passed out on the sofa again. Nancy has been doing the ironing, so Sienna quite calmly walks over and puts the iron hot-side-down on one of Oscar's baby-grows. She effectively sets fire to The Dog flat!"
What was it like to film these scenes?
"It was so exciting! I've never filmed a fire before, so it was quite fun to see how they set it all up. It sounds silly, but I was actually quite surprised that it was a real fire! To be part of all that was brilliant."
Does Sienna feel any sympathy for Nancy when her mother dies and she has to go to Canada for a while?
"At that point, Sienna is thinking more selfishly. She's just pulled this stunt with the fire and made Darren aware of who he's married to, so she feels like she's achieved what she set out to do. However, when the news comes through that Nancy's mum has been killed in a car crash, it brings Nancy and Darren back together again.
"Darren instinctively wants to support his wife and take care of her, so on a selfish note, it gets in the way of Sienna's plans and schemes! I don't think she has much sympathy for Nancy in that situation."
Darren and Nancy are a much-loved couple, so are you nervous about how fans might respond to Sienna's games?
"I am so nervous! (Laughs.) Obviously everybody loves the Osbornes, and Darren and Nancy are a really sweet couple when they're working well. I think the problem is that the character of Sienna is quite a closed book. People haven't really got to know her yet, as when she first came in, she stood back and observed everything rather than showing too much of herself.
"It's only since Sienna has struck up this friendship with the Osbornes that she's started to come out of her shell a little bit. I think the audience are just starting to warm to her now, and they like the friendship between Nancy and Sienna, so I'm very nervous to see what happens when Sienna wrecks all of that! The audience might be very disappointed in Sienna after finally putting their trust in her!"
This is a long-running storyline, so are you excited by where things are heading in the long-term?
"Definitely! With it being quite a slow-burn storyline, there's lots of opportunity for me to create quite a complicated character. It's not as black and white as it seems, as Sienna has her reasons for everything that she does. It's quite exciting to know that this is going to go on for a while longer. We're going to see it through, and hopefully by the end of it, the audience will have a much better idea of who Sienna is."
Sienna isn't too happy to see Patrick and Maxine together either! Will she continue her attempts to split them up?
"I think people have been a bit confused by that to begin with, as people have even been asking whether Sienna is in love with Maxine! It's more that Sienna has grown up just with her father, and they haven't really had anyone else around. She's become so close to Patrick and is so used to having all of his attention on her, so now she feels a bit abandoned.
"When Sienna sees Patrick giving all of his attention to Maxine, she finds it very unsettling. I don't think it's going to be an easy ride for Maxine with Sienna!"
What's it like to have Jeremy Sheffield as an on-screen father?
"I absolutely love Jeremy and couldn't have wished for anyone better to play Sienna's father. I remember that I used to have a massive crush on him when he was in the Natalie Imbruglia 'Torn' video! If somebody had told me at the time that one day I'd be on Hollyoaks and he'd be playing my father, I would have literally died!
"Jeremy is great to work with and he's such fun. He always knows what he's doing, so he's such a pro."
How did you get into acting?
"I've been doing it since I was at school, really. I had a really fab Drama teacher called Mr Lewis, who really got me into it. I went off to university to study English Literature and Drama for a while, and then I went off to drama school.
"I've always had acting as my plan and have always been very much involved in it, but I've only been working professionally for the last six years. It's mostly been on feature film, theatre and commercials, so this is my first soap role and it's a whole different ball game for me. I'm finding it really exciting!"
> Read more 'Hollyoaks' spoilers and news
Hollyoaks airs weeknights at 6.30pm on Channel 4, with first look screenings at 7pm on E4.
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