Karen Pirie star confirms new drama The Ridge undergoes a huge change after episode 4 twist which viewers need to see

All six episodes of new thriller series The Ridge are now available on BBC iPlayer, and for those looking for their next binge watch, it could be just the ticket.

In fact, star Lauren Lyle has implored that fans make their way through to the fourth episode, telling RadioTimes.com exclusively that there's an enormous twist which is why she wanted to do the show in the first place.

The series follows Lyle's character, Mia, a Scottish anaesthetist and secret opioid addict who leaves behind some serious issues at her work to attend the wedding of her estranged sister Cassy in New Zealand.

However, on arrival she’s shocked to learn Cassy has fallen from a mountain ridge and died – something she believed may have been murder, rather than a tragic accident. She therefore sets about hunting for the killer.

In her interview, Lyle said: "Episode 4, there's a huge reveal of who Mia actually is, and it's basically the reason I wanted to do the show. At the end of episode 4 she says something and says what she's been doing with her life, and it's like the anti-hero thing, and it's so fun. And getting to do that at the top of a mountain and reveal it, it completely turns the show. It turns it into why I signed on.

"There’s that, and then one of the final scenes of the whole show, she does something so mad. It took all day to shoot again at the top of a hill, and I just got to go mad in episode 6. That, again, is why I signed on. The first two to three episodes, there's bits, but it's not everything as to why. I just need people to get to episode 4."

Lyle also suggested that the tone of the drama shifts in the third episode, and that it "ramps up" after the first two instalments.

"From episode 3 onwards, the real intensity of the drama starts, and it really turns," Lyle said. "Mia becomes kind of turns evil in lots of ways. So I really want people to stay until then, to see that turn, because it then ramps right up into something that I think you really don't expect from episodes 1 and 2.

"I feel like when you hit episode 3 and 4 as well, I honestly feel like it becomes a different show in some ways. I almost want people to really know that, because I feel like it becomes something really, wildly different in a really fun way."

Lyle also spoke about the differences between Mia and the role for which she is most famous, Karen Pirie, saying this new character is "weird" and "strange".

The Ridge is available to stream now in full on BBC iPlayer. It will also air on BBC Two from Thursday 23rd October at 9pm.

Add The Ridge to your watchlist on the Radio Times: What to Watch app – download now for daily TV recommendations, features and more.

Check out more of our Drama coverage or visit our TV Guide and Streaming Guide to find out what's on. For more TV recommendations and reviews, listen to The Radio Times Podcast.