For Her Sins fans stunned over huge change in Rachel Shenton during first episode

For Her Sins kicked off on Channel 5 this week and fans are already impressed with Rachel Shenton, who plays the mysterious role of Emily Furness.

The four-part thriller follows high-flying lawyer Laura Conroy (Jo Joyner) who is struggling to balance all her commitments since becoming a mother. She has two young children and her husband is often away on business, so she has to juggle a lot of responsibilities.

She thinks her luck has changed when she befriends Emily, and she finally has someone to talk to about motherhood and feels less alone, but there's a lot she doesn't know about her new friend.

Throughout the first episode, it becomes clear that Emily has some connection to Laura, with upsetting flashbacks to images of a drowning child. But who is the child, and how does it relate to Emily and Laura?

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There are lots of questions to be had as Emily continues to get closer to Laura, befriending her and earning her trust while plotting away in the background. 

At one point we saw her on the phone telling an unnamed caller "It's definitely her", so something's going on!

We're not entirely sure of her full intentions yet, but Rachel's performance has got fans hooked as she takes on something different from what we're used to seeing her in.

Many fans pointed out that it was "strange" to see Rachel Shenton playing a "baddie", considering her famous role in All Creatures Great and Small which sees her as a positive, enthusiastic farmer's daughter named Helen Alderson, so far removed from her For Her Sins character.

There's also been praise for former EastEnders star Jo Joyner too, with everyone keen to learn more about what happens over the next three parts.

Teasing more about what to expect from Laura and Emily's relationship, Jo Joyner told What to Watch: "Laura's at such a low ebb when we meet her, in her home life, and it's so out of character because she's used to being in control and in charge at work. 

"What Emily does really well is find her at that point and then just pulls those little threads every now and then — gaslighting her, ultimately, pretending to be the best thing in her life at the moment. So it's a really complex relationship, and it's written really well, and one of the things I loved about it was how she chips away at Laura's confidence without Laura even knowing."

For Her Sins continues tonight, Tuesday, June 6 at 9 pm on Channel 5. Episodes are available on demand via My5.