Joe (Derek Riddell) renews contact with Christine to talk about his father's will, but his presence sends the troubled English teacher into a spin with big consequences.
When Joe shows an interest in getting to know his son, Christine falls off the wagon in spectacular fashion - fearing she could lose Connor forever.
Digital Spy recently caught up with Laurie Brett, who plays Christine, to hear more about the storyline.
You've gone from one big TV show to another by moving from EastEnders to Waterloo Road. How have you found the experience?
"Christine was just such a gift of a part to be offered, especially so quickly after playing Jane Beale for so long. Jane was a very loved character, so it was great to be given the chance to play Christine, who is such a different woman. I always saw Jane as an 'every woman' character - she worked hard, she had a good heart and she was normal most of the time, although with a lot of madness around.
"On Waterloo Road, though, Christine is the madness! I remember my agent saying, 'You can't not play Christine, because it's just such a brilliant part'. I just feel really lucky that the role happened to be out there when I left EastEnders. The transition from Jane to Christine has been great, and I'm very lucky to go from one to another in such a quick timeframe."
What kind of a reaction have you seen to Christine?
"I was initially quite concerned about what the reaction would be. When I was playing Jane, everybody who stopped me in the street was so lovely and nice, because they liked her. But when I started filming Waterloo Road, there were a couple of times where I wondered whether I'd be hated and loathed, especially in the first ten episodes when Christine was drinking all the time and was so vile to her son.
"But I did a lot of work on Christine. She is a nasty drunk, but she's also a damaged woman and I worked very hard to bring out some vulnerability in her. People have loved her, and I think they've even loved her when she's been a bit drunk, loud and nasty. I was really surprised at the response - pleasantly so! I see a lot of people saying, 'I don't know who I feel more sorry for - Connor or Christine?' That's exactly what we were aiming for."
Did you do much research into the alcoholism storyline, or did you leave that to the writers?
"A lot of it I left to the writers, because they've written brilliantly for Christine. I think they've worked really hard on the complexity of the character. The role was always planned to be that way even before I joined, so a lot of it was in the writing.
"I did feel a responsibility to do quite a bit of research on alcoholism, but a lot of it is also instinctive - it's acting and you've got to go with what you're given in the script. We've all seen people drunk and you can draw on that. Also, after watching Steve McFadden and Linda Henry do drunk scenes so well on EastEnders for so long, I stole lots of things from those two!"
How does Christine react when her ex-husband Joe arrives this week?
"It's a huge shock to her! I don't even know if there's a word big enough to describe what this means for Christine. She hasn't seen Joe since she was pregnant, but she really loved him. She never expected him to come into her life ever. Now that he has, it's her worst nightmare - she's confronted by everything she tried to forget. It's also just when she was on the up, so it couldn't have happened at a worse time."
Why is Joe back?
"Joe is back because his father has died, and Christine has been gifted half of a farmhouse in the will. Joe has come back to ask her to sign the farmhouse over to him. He hasn't come back to see Connor or Christine, he's come back to get what he thinks is rightfully his. It's the only reason he's returned.
"Even knowing that cuts like a knife for Christine. There's a small part of her that wishes Joe genuinely wanted to see her, but that's not the case - it's purely business."
Pictured: Christine and Joe.
How does Connor feel about Joe being back?
"At first Connor doesn't know that Joe is his father, but Christine has to tell him what's going on, because Joe suddenly says that he wants to see the boy. He may have an ulterior motive, but Christine fears that she might lose Connor forever…"
Did this episode present a good opportunity for you to explore Christine's past?
"Definitely. I'd known all along that things in her past had triggered her problems, but then when I got to know what it was, I was really excited to play it. I was also thrilled that Derek Riddell was coming in to play Joe, because he's such a lovely actor. I knew the scenes would be great with Derek and that he'd be easy to work with.
"I think we'd reached a point in the series where it was time for the public to understand Christine a little bit more. They'd accepted her and loved to hate her, but it was time for them to feel for her and get to know the real reasons why she's so unhappy and damaged. It was a great episode and a great opportunity.
"It should hopefully be moving to watch, as we see Christine really break down in this episode. It was really, really hard work to get it right - but very enjoyable."
What is Shane O'Meara, who plays Connor, like to work with?
"Shane's lovely! He's such a sweetheart and we clicked straight away. We rehearsed a little bit together before we started filming, and he's just a lovely young man who's eager to learn - he wants to get better and better all the time.
"Shane is also so unaware that he's gorgeous - it's absolutely endearing. I remember the first time I saw him, I just said, 'Oh my God mate, you're going to get so much attention!' I think he looks like a young John Travolta on screen sometimes. I love him like a real son, I really do. I'm sure he'll go on and do some great things."
Pictured: Connor and Joe.
Do Shane and the other younger cast members approach you for advice?
"They do come to me for advice, and sometimes I just give it to them whether they want it or not! (Laughs.) I was very fortunate all along my career, as I've worked with really great actors and actresses who have given me pearls of wisdom and advice along the way. It's nice for me to be able to do that for other actors who are coming up. I think you should pass on what you know and help others, as it's a nice thing to do."
Would you consider returning to EastEnders, or do you feel like you've closed the door on Jane?
"I would never say never to going back, as I loved playing Jane. She's Bobby's mum and it will always be that way. I think Jane is a character who could go back at some point in the future - it wouldn't be implausible. I think Jane and Ian will always love each other, it just went so wrong and she'd had enough in the end!
"Jane will always have ties to the Square as she knows everyone there. It's not out of the realms of possibility for the future, but at the moment I'm quite happy playing Christine. It all depends on timing and jobs and if they ever wanted me - they might be thinking 'good riddance'!"
We know you film Waterloo Road really far in advance, so are you covering any happier times for Christine at the moment?
"What I'm filming at the moment is a very bittersweet ending to series eight. There's some good things, and there's some bad things! It's not just the drinking that makes Christine the way she is - there's a fireball in there either way. She's never going to have an easy life!"
> Read our spoiler for the next episode of 'Waterloo Road'
> Read more 'Waterloo Road' spoilers and news
Waterloo Road airs on Thursdays at 8pm on BBC One.
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