Where in life is Rose at the start of series three?
Rose is coming to terms with the fact that she won’t be able to naturally conceive a child, and previously to episode one, her and James (Rudi Dharmalingam) have decided to adopt. So at the start we find her grappling with her feelings about that and her last-minute panics about doing it. She’s helping her sister Nina, as a really important part of a baby’s life by being an aunt, and is getting self-worth from that, realising that to parent you don’t necessarily have to be a mother.

There’s a realness to Abi’s writing, were there any particular moments that you related to this series?

Oh yeah, it’s a real privilege to be able to work on Abi’s scripts! She’s particularly good at twisting a scene right at the end so that it goes to a place you didn’t think it would. And she often does that with humour too.

The dynamic of the Defoe sisters evolves further in series three - as Rose is the younger sister does she defy the cliched myth about younger siblings, and actually holds everything together?

One hundred percent! I think Rose is kind of like Cordelia in King Lear in some ways. She’s obviously on the outside of some of the central action but when it comes to it, I think she holds Nina and Hannah together in a way that is quite unexpected sometimes, and shows strength that you wouldn’t necessarily expect from her sometimes because she’s the flaky one, or the younger one. She’s not the lawyer! But Hannah and Nina’s lives tend to fall apart a bit and very often Rose is there holding them together.

As this is the final series, what is going to be the hardest to let go of Rose?

Ah it’ll be that family dynamic! Because as with all these things, life imitates art and you develop these relationships off-screen as well as on, and I’m going to miss that. I’ll miss working with people I really love; we’ll still stay in touch obviously and we are very much in touch, but getting to come to set every day and see those people and just hanging out together, is the joy, the dream. Not only that, the material that you’re working on is special too and so the people behind the camera, Abi, Jane (Featherstone), Lucy (Dyke), Sister, it is like being in a family. I’ll really miss that.

Without sounding shallow, will you miss those gorgeous houses, the locations?

Funnily enough, my favourite location isn’t Hannah’s house, even though it’s absolutely enormous and bigger than any house I’ve been in in London. It’s bigger in real life than it looks on screen as well! But it’s kind of awkward to film in, there’s always tricky things to manage there. I really loved the church as a location, and Noble Hale Defoe, those offices this season were amazing! I didn’t get to go there very much because Rose doesn’t, but that was fun because they completely built the offices out of nowhere.

And how was that last day of filming, knowing The Split was coming to an end?

It was emotional, it really was. We were all really sad but elated too, and there was a big party and that was great, and we celebrated it but there were tears! I do feel that The Split has been a really beautiful triumvirate and that was always Abi’s intention and I think the end of series three is great. It’s what it should be.