'Doctor Who' guest star Foxes talks 'Mummy on the Orient Express'

How busy has Foxes been of late? Busy enough that the British singer-songwriter neglected to tell her family she was making a guest appearance alongside Peter Capaldi and Jenna Coleman on this Saturday’s episode of Doctor Who, the tantalizingly titled “Mummy on the Orient Express.”

“In all the madness I’d forgotten to tell my family,” explains the Brit, who released her debut album, Glorious, last May around the same time she filmed her appearance on the long-running time travel show. “What’s funny is, my sister’s husband is an acting agent and he looks after Jenna, randomly,” she adds. “He visited the set, and found out through that, and then told my sister.” Was her family excited when they finally heard the news? “I think it feels like one thing in a bunch of things,” she says. “They’re just getting used to me saying [things like], ‘Oh, I forgot to tell you, I’m going to be in an episode of Doctor Who!’ But I’m excited. I want to have a Doctor Who-themed screening night. It’ll be a funny one!”

Below, Foxes talks about shooting her role on “Mummy on the Orient Express,” which screens on BBC America this Saturday at 9pm ET.

EW: So, tell us about your Doctor Who experience.

FOXES: It’s funny, actually. I was in between a lot of promos so it feels like I dreamed it. It was very quick, but very very fun. I basically play a singer. I didn’t know they were going to ask me to not only do a song but actually be in the episode, so that was quite amazing.

What song do you perform?

I’m can’t say that! But it’s something quite different for me.

How did you get the job?

I was doing a gig in one of the BBC buildings in Liverpool and behind me was a Doctor Who conference going on. I went back—and I probably shouldn’t have been there—but I was snooping around. I got talking to, what I didn’t know at the time, were the producers. “What’s happening here, then?” “It’s a Doctor Who conference.” “A-maz-ing!” I was fan-girling over the show. I guess they watched my gig without me realizing and then a couple of weeks later got a call asking me to do a song for them.

What was the shoot like?

Really exciting. As I said, it felt a bit dreamy because it was amongst the promo week when the album came out. But it was such good fun. Everyone was really welcoming and treated me like family. It was really sweet because they could have thought, “Oh, who’s this girl strolling in?” But it was so lovely. I already know Jenna. [But] she actually didn’t know I was doing it. She went, “What the hell are you doing here?” That was quite funny. And to be in the TARDIS was one of those moments where you’re like, “This is a dream. Am I going to wake up?” I couldn’t believe the buttons all actually worked and all the little things in the TARDIS actually have a purpose. It’s quite mind-blowing. I just think they must have the best time. What a great place to work! I just resorted to being a child again. There’s just lots of buttons to press! I was being quite geeky.

What’s Peter Capaldi like?

Very charming. When I met him I was like, “I’m such a big fan, it’s an honor to meet you.” And then he was like, “I’m a big fan, actually, of you. I’ve got your album.” I was like, “Say what?” You don’t know who I am! You’re lying!”

Has this experience encouraged you to do more acting?

I love music and music will always be my first and foremost. But I definitely felt like it was kind of a fun hobby, something that you don’t do every day. So I wouldn’t rule it out. But I’m not going to go off and try to be an actress any time soon.

You’re on tour with Pharrell at the moment?

Yes. It’s been a proper whirlwind. He is literally the man. He’s so lovely. Considering who he is, he’s very down to earth. He’s all about his craft, and putting out a really good message, and I really respect that.

But does he know about Doctor Who?

[Laughs] I haven’t talked to him about Doctor Who. I don’t think he does, to be honest, no.

He actually seems like a character the Doctor might come across on some distant planet.

You think? I’ll pass that one on! [Laughs]

See the trailer for “Mummy on the Orient Express” below.