Another interview of our lovely Lily with RadioTimes this time. Lily talks mischief, drinking tea with Maggie Smith and being inspired by Downton Abbey fashion.

“Maggie Smith’s just been one of my idols growing up… so now to be sitting drinking tea with her is slightly bizarre!”

Lily James plays Lady Rose, Downton Abbey’s new resident trouble maker. Before the drama returns to ITV, we sat down with the 24-year-old rising star to find out what’s in store for her in series four…

What was it like to join the cast after almost three series?
It was really overwhelming at the start of the series. I’ve loved the show. But everyone was really welcoming and really encouraging and really warm. Especially this year, I feel totally a part of it now. And it didn’t take long. My first day was like the first day of school, I was like ‘Like me! Like me!’

Can we expect mischief from Rose in the next series?
She wants to shake up her own life, so I guess that has an impact on the household. She puts herself in positions that are really inappriopriate and searches for fun in places that weren’t allowed at that time for young girls.

She’s risking her position and she’s risking being with the family and Downton, which she loves, so when she does try and have fun she has to try and rein it in.

Does this fun have anything to do with a certain jazz musician…?
Ah. [laughs] You’ll have to wait and see.

Okay, we won’t talk plot spoilers, but did you have an idea of where you wanted Rose to go in series four?
All actors want to sort of show a rounded character… so I was hoping that you’d see lots of different sides to Rose. You know, obviously, she’s the party girl and she’s sort of seeking an adrenaline rush, seeking excitement, but there is also lots of other stuff going on so that’s what I was hoping you’d see.

Do you ever try and second guess where the plot is going?
I just never know what Julian’s going to do, I swear! You never would have thought that Matthew Crawley would be able to walk again so you’re never going to know what’s going to happen!

I thought some stuff reading initial scripts… and I was so wrong! Sometimes stuff happens and you wish it would continue and it doesn’t – new elements or factors come in – so it’s really exciting as an actor getting the new scripts and reading them.

Rose gets to wear some lovely costumes…

The costumes are just beautiful. Caroline’s [McCall, the show’s costume designer] a genius.

[Rose]’s very cutting edge in fashion. She’s wearing stuff from Vogue at the time, a lot of knitwear. It’s really changed my fashion sense. I’m kind of going for more boyish… dropped hemlines and stuff. It’s rubbing off on me.

Do you ever get to keep any of it?
No, they are original pieces. [Caroline] goes to Paris, she goes everywhere.
I’d kind of like to wear one of them on a red carpet maybe one day, but then you kind of also would be like ‘I’m done with it, I want to wear jeans!’

Are you worried about damaging any of the costumes?
They get ripped a lot actually. The beads are so delicate that everytime you sit down you shed beads!

You’d had quite a few scenes with Maggie Smith. What’s it that like to work with her?
She’s just been one of my idols growing up… I even played Desdemona in the theatre a couple of years before this an I like literally watched her version of it over and over again. So now to be sitting drinking tea with her is slightly bizarre! She’s wonderful and she’s just incredible. Every time I get scenes with her, even a group scene with her, I’m like, ‘yay!’

Do you feel like you’ve learnt anything from her?
She’s just present. She just listens. She’s so alive in the moment and everything’s fresh. I don’t know how she does it, I really don’t. I can see she’s doing it, I don’t know how! But maybe it will happen with experience.

Rumour has it there are a few big parties in series four. Do you like those big set scenes?
I prefer the one-on-one scenes just because I find it easier to lose myself in the moment. But the big set scenes have a whole other value because they are so beaufitul and decadent. Honestly some of the locations we’ve had this year are bigger and better than you could dream of and… [with] all the extras and the costumes, you really feel like you are going back in time. Aesthetically and for that kind of magical sensation it’s the big set scenes, but as an actor I prefer it when it’s kind of one-on-one.

Are you keen to stay for a fifth series?
Yeah, if it happens and if I’m involved with it it’ll be amazing. I think there’s room for more and I really love it, I think everyone does.