Airing on E4 last night and on Channel 4 this evening (June 29), a game-changing episode saw Brendan Brady (Emmett Scanlan) discover a lifeless Lynsey on the sofa at their flat - sparking a whodunit storyline.
As show bosses kept Lynsey's exit completely under wraps before broadcast, fans have been left stunned by the tragic turn of events.
Karen Hassan, who played Lynsey, today gave Digital Spy a call to chat about her character's fate and her future career plans.
How do you feel now that your time at Hollyoaks has come to an end?
"I feel really sad, actually - especially as I had my leaving party last night! I'll be really sad to say goodbye to everyone, but I've made some really good friends there and I'm sure we'll all stay in contact. I hope the show will go on and do amazing things."
Was it your choice to leave Hollyoaks now?
"It was a mutual decision, as I was going to be leaving in August anyway but they moved the storyline forward a bit. That's how it is sometimes, so there's no hard feelings whatsoever. I was more than happy with my exit storyline as I always wanted Lynsey to go out with a bang, and she did!
"I think the producers have definitely given Lynsey the send-off that she deserves, so I'm really grateful for that."
Did you have a good turnout for your leaving party?
"Definitely - some people were working, but there was a huge amount of people that turned up last night, so it was really lovely. My friend Claire Cooper, who plays Jacqui, organised it all, God love her! I walked into the restaurant and there were two massive long tables full of people who had come to say goodbye. We partied the night away, so it was really good!"
What has the reaction been like since Lynsey's death aired on the E4 first look last night?
"It's been absolutely crazy on Twitter. I've had lots of messages saying 'Why have you left?' and people have said they're sorry to see the character go. It's lovely to hear people say that Lynsey was their favourite character and stuff like that, so I've had some really nice feedback. A lot of people seem quite shocked by the whole thing!"
Nobody had a clue you were leaving, so was it difficult to keep such a big secret?
"It was, because people kept asking me about my plans for the future and whether I was happy to stay on at Hollyoaks. I already knew that I was leaving, so it was hard not to tell everyone, but the important thing was to stay true to the story.
"I kept that in the back of my head, because we did want this big shock factor. I had to play along with things and keep it to myself for a bit. Obviously my family and friends all knew that I was going, but we had to keep it a secret for the audience."
Was it emotional to film your last scene?
"It was! I was given a really juicy last scene. It's one that the audience hasn't seen yet so I can't really talk much about it, but let's just say that it was very traumatic and tumultuous, so it was a good one to go out on!
"It's going to be one for the audience to look forward to. I had my last day on Monday, so it's all come around quite quickly - I left Hollyoaks on Monday and had my on-screen death on Thursday night! It's been like ripping the plaster off quickly, really."
Have the producers kept you in the dark about where the story is heading, or do you know who killed Lynsey?
"Yeah, I know who did it! I couldn't possibly say because I don't want to spoil the ending for anyone, but there's definitely a few people who are going to have the finger pointed at them.
"It'll be nice to see if the audience can figure it out for themselves. I'll definitely be tuning in to see how it all plays out and keeping up to date on Twitter to see if people are thinking along the right lines…"
You mentioned filming a scene that the audience hasn't seen yet, so is there going to be a flashback to the murder at some point?
"Possibly! I don't know if I can confirm or deny that, but what I can say is that I've done a few juicy scenes that haven't been on screen yet.
"So you'll have to wait and see whether those are flashbacks or something else, but I think the audience will definitely feel like they've got the ending they were looking for. Some of it should be on screen next week, and then more a couple of weeks after that."
Who in particular from the cast are you planning to stay in touch with?
"All of them, really! I mean, certainly everyone who showed up last night for that dinner. I just wish everybody all the best and I'm going to miss everyone. There's a few people who I'm sure I'll still see every week and stay friends with them. You never know, Hollyoaks do bring people back as ghosts every now and again, so maybe it isn't the final farewell!"
You've had a fantastic couple of years on Hollyoaks. What have the highlights been?
"I think the first would probably be when I was first cast in it. I remember walking through the doors and just being so super excited and meeting everyone for the first time - that always sticks in the memory.
"Another is when Paul Marquess, our former producer, brought me up to the office and told me, 'You're going to be involved in this really big storyline'. He told me the layout of the plot and I was just buzzing on the way home!
"And then the exit too, because I really think Lynsey got the send-off she deserves. Those three memories really stick out in the head, but there are so many from the last two years that it's hard to pin-point them. It's been crazy but brilliant."
Will you be staying in Liverpool for now?
"For the time being, I'm staying in Liverpool, but I'll be moving to Cardiff for three weeks to do some filming there from Monday. I'll just go wherever the wind takes me, really! I'm up for moving anywhere."
We'll see you back on our screens in BBC Two thriller The Fall this autumn. What was it like to film the show in Belfast?
"Oh, it was so good. They're editing it all together now and I've been hearing some really good feedback. The word is that the stuff we've done has gone down really well, so I'm so excited to see how it's all put together.
"I love thrillers, so watching it as an audience member would be exciting enough - but to be involved in it is even better. I'll have other projects down the line too, so hopefully they'll all come on screen at a similar time."
You're playing Annie Brawley in The Fall, so is she a small or big role in the show?
"It's actually a part that will hopefully develop more in the second series. But the scenes that I've done are quite hard-hitting, so sometimes even if you don't have the biggest part in a show, you can still make the impact that you want. So I'm more than happy playing that part - I really enjoyed the character."
Are you looking forward to getting back out there and auditioning again?
"Well, first of all I've actually got a few episodes in Casualty - that's what I'm filming in Cardiff and I start there on Monday. So I'm back into the acting game straight away, which is great. I also went for an audition last week, which was scary but brilliant! So I'm waiting to hear back from that as well. I can't wait to start auditioning and going for different parts."
It sounds like you have quite a bit of TV on the way. Would you consider film and theatre as well?
"I would definitely love to do some film and theatre too. That's what I did before I joined Hollyoaks - I did small parts in films and some theatre as well. I think theatre definitely gives you your training as an actor, so I definitely want to get back on the stage at some point. And I suppose film is every actor's dream, so hopefully the opportunities will come up for me - watch this space."
How would you like Lynsey to be remembered?
"Serial killer hunter extraordinaire?! Probably the girl next door with a big heart, Cheryl's bessie mate and the girl who could never really find the man of her dreams!"
> 'Hollyoaks' airs shock death
> Read more 'Hollyoaks' spoilers and news
Hollyoaks airs weeknights at 6.30pm on Channel 4, with first look screenings at 7pm on E4.