Michelle catches Ryan (Sol Heras) red-handed in the toilets at The Rovers following a tip-off from David Platt, and is devastated to see how low he has stooped. Ryan later insists that the incident was just a one-off, but will Michelle be fooled?
Digital Spy recently caught up with Kym Marsh, who plays Michelle, to hear more about the storyline.
Are you glad to see Ryan back on the cobbles?
"Oh, I'm absolutely delighted that they've brought Ryan back - it's fantastic. It's another side to Michelle's life that's been missing for a little while now, so to have him come back is brilliant. He obviously brings a fair share of problems back with him, which has been enjoyable to play."
Has Sol been settling in well?
"He's settled in brilliantly. Obviously he was nervous on his first week, as everybody always is, but he's doing really well. It's got to be difficult coming in to play a character who has already been established by another actor.
"But I think it made things easier that Ben Thompson, who played Ryan before, had been gone for two years. That left room for Sol to put his own characteristics into the character, which Ryan may have picked up along the way. That's worked out well, because Ryan's personality has changed so much since we last saw him."
Have you been showing Sol the ropes during his early days on the show?
"Well, when you come here it can be quite confusing, as you have to check what days you're working, how many episodes you're in and what your call times are, so I did try to help him as much as I could with that side of things.
"I gave Sol a call to congratulate him once I knew he'd been cast as Ryan, and said that I'd be there if he needed anything. Everybody else here has been helpful with him, too - the guys in the office are so good at that kind of thing, so you're left with no confusion."
How does Michelle react when she discovers that Ryan has a drugs problem?
"She's devastated, angry and hurt. When Ryan went away to university, he was someone who always confided in her and she felt so close to him, because they'd grown up together in a way. Michelle was a very young mum and they've always been so close. It's like a slap in the face for Michelle to realise how much he's changed."
Have you enjoyed tackling such a topical subject matter?
"It's been a really tricky storyline, but it has been brilliant to do. I've filmed a lot of scenes recently where I've been raging! It can be quite hard to come down from that when you go home, but it's been really enjoyable too. I'm fortunate to be a part of this storyline, and hopefully we'll do it justice. It's a serious issue, so hopefully we'll have hit the nail on the head with it."
How have you prepared for the storyline?
"Well, the writers are always very, very good when it comes to research, so when something is written on the page, you can bet your life that they'll have gone through it with a fine tooth comb. That's the main thing, but obviously being a parent myself, I'm also able to imagine how that might be and how I would feel in this situation.
"Luckily, I don't have those issues - my son is almost 18 now and it's not his personality to be heading down that road, thankfully. But that doesn't stop you from being able to put yourself in that position as a parent, because I'd be devastated to be in Michelle's situation in real life."
Does Ryan apologise to Michelle when his drug habit is exposed?
"No, he fails to see his problem in the beginning - he doesn't see it as a big deal and he probably doesn't feel like he has anything to apologise for at that stage. So we're going through all the different stages - the lying, the denial and all the rest of it. It's going to be a journey for all the characters involved."
The situation also leads to some reignited chemistry between Michelle and Steve. Could that go anywhere?
"You never know - in Corrie it can go anywhere, can't it? Michelle has already been with Steve before, so if they were to get back together, we don't know how long that would be for and whether it would be plain sailing - because it never usually is! So who knows?
"For now, I think Steve is just doing his best to support Michelle throughout this situation with Ryan. He's absolutely there for her no matter what she needs, and he's trying to reassure her. He's her shoulder to cry on, really."
How is Michelle coping at the factory without Carla around?
"Life at the factory is plain sailing for Michelle at the moment - she enjoys being there and she enjoys working with Rob. I love that side of Michelle, because we have a lot of fun filming in the factory.
"There's a lot of light and shade going on in this storyline - it's not all going to be bleak for Michelle, as there's a lot of comedy aspects that run through other parts of her life. Michelle gets some relief at the factory and is able to get her head into work."
Would you say there's a chemistry between Michelle and Rob, too?
"There is a little bit of chemistry between them, but I don't know if that would ever go anywhere or what that situation is. But there is definitely a spark there between them. I think we'll have to wait and see with that one!"
Have you also enjoyed working with Marc Baylis, who plays Rob?
"Marc is fab. From the second he walked onto set, he fitted in like part of the furniture. It's funny, because we obviously see a lot of people come and go at Corrie over the years, and you can tell instantly who's going to stay.
"Marc and Sol have both been dropped right into the deep end when it comes to storylines. Sometimes I think that's better, because you don't have time to think - you've just got to get on with it. It already feels like we've known Marc forever and he's so easy to work with. He's already like an annoying brother to me!"
Is it strange not having Alison King around on set at the moment?
"Oh yeah, we miss her so much. She's such a great person and she's nothing like Carla. She's completely bonkers in the best possible way, and she's one of my best friends. I get on so well with her, so I'm missing her loads."
Keith Duffy recently said that he'd be interested in returning as Ciaran at some point. Would you like to see him back?
"Definitely. I was gutted when Keith left, because the writers had such good ideas for our characters. I think the plan was always to keep them together, because they were going to have a very tempestuous relationship and it was always going to be like that.
"Keith left because he has a lot of family commitments, which is understandable, but it was a shame because we'd only really begun with our storylines and then he was going. So I'd love to see him come back. Whether they'd put us together again is another matter - it depends where Michelle is by then. But I'm sure him returning would stir things up."
The papers also said recently that you'd landed a new three-year contract with Corrie. Is it true that you've signed up for that long?
"Well, I have just signed another contract which will take me up until at least next June, but after that, we'll just have to wait and see. No-one ever really knows how long they're going to stay for past a year, because that's the contract that you sign. But I'm definitely here for another year!"
> Read the latest 'Coronation Street' spoilers and news
Coronation Street airs Michelle's discovery about Ryan next Monday (July 30) at 7.30pm and 8.30pm on ITV1.