Get me home!"

“I think I’d be much more like Belinda in real life thinking, ‘Who is this?

Why am I shackled to a madman?

The Doctor (Ncuti Gatwa) and Belinda Chandra (Varada Sethu) in Doctor Who

Ncuti Gatwa and Varada Sethu on ‘Doctor Who’ season 2.Credit:Disney

Why am I a prisoner on this runaway train?

Get me home!’

She’s very much aware that people die around the Doctor.

Belinda Chandra (Varada Sethu) in Doctor Who

Varada Sethu in the ‘Doctor Who’ season 2 premiere.Disney

It’s trouble.”

“I was in awe of her performance every day,” Gatwa says of his new costar.

“Varada is just an incredible actor.

Belinda Chandra (Varada Sethu) and The Doctor (Ncuti Gatwa) in Doctor Who

Varada Sethu and Ncuti Gatwa on ‘Doctor Who’ season 2.James Pardon/BBC Studios/Disney/Bad Wolf

Incredibly grounded, so truthful, and gives so much to the text, and to other actors.

It’s just incredibly enriching to work with.”

And still after 50 viewings, I was watching her thinking, ‘God, she’s good.

Doctor Who - Season 1 Picture Shows: Episode 1 The Doctor (Ncuti Gatwa) and Ruby Sunday (Millie Gibson)

I love her!'"

The preliminary casting process for Belinda was already underway by the time cameras rolled on “Boom.”

“We’d done a lot of auditions and it wasn’t quite clicking,” Davies explains.

Doctor Who - Season 1 Picture Shows: Episode 1 The Doctor (Ncuti Gatwa)

“That notion of having her be an equal with the Doctor was very hard to cast.”

Suddenly, Davies realized that the answer was right in front of him.

“It just clicked.

Ruby Sunday (Millie Gibson) in Doctor Who

Millie Gibson in ‘Doctor Who’ season 2.Lara Cornell/BBC Studios/Disney/Bad Wolf

I went, ‘Well, I can.

We could just bring her back!'”

“That was the fastest ‘yes.’

Conrad (Jonah Hauer-King) Ruby Sunday (Millie Gibson) in Doctor Who

Jonah Hauer-King and Millie Gibson on ‘Doctor Who’ season 2.James Pardon/BBC Studios/Disney/Bad Wolf

We all loved her.

So it was actually one of the easiest pieces of casting we’ve ever had.

James Pardon/BBC Studios/Disney/Bad Wolf

Sethu tells EW that she was ecstatic when she received her invitation back into theWhoniverse.

“It was the best feeling ever,” she says.

“I couldn’t believe I got to come back.

That’s when the phone call came.

“It just felt totally unbelievable,” she says.

I was so, so happy to be back.”

Belinda’s introduction on the show happens somewhat perplexingly.

“For once, it’s the Doctor actually chasing after her.

You don’t have to wait for the end of the series for that.”

“I’m not just saying this: It really took my breath away,” the actress recalls.

“It’s so much bigger than you think it’s going to be.

It obviously looks massive on screen, but then when you’re actually in it, it’ssoexpansive.

It was such a special moment.”

“The whole program was aiming to get there, and yet there’s something wrong with that day.

Lara Cornell/BBC Studios/Disney/Bad Wolf

Belinda isn’t the only companion who’ll turn up this season.

“What happens to life back on Earth?

And believe you, me, that’s going to bring some PTSD with it.

“He’s absolutely delightful and such a part of the team,” Davies says.

And for Conrad, it’s: How on Earth do you live up to the Doctor’s ideal?

This woman used to keep company with the most exciting man in the universe.

How can he be the Doctor in her eyes?

And that’s a story that gets very complicated.”

Davies says that Gibson will also return for the season finale.

“Lots more Ruby Sunday to come, I promise you,” he says.

“She’s back from the moment she left.

She never actually left, in fact.”

The showrunner also believes that Gatwa continues to outdo himself with every episode.

“I think he grows every day,” Davies says.

The latest Christmas special showed the Doctor’s loneliness.

“The Doctor’s in a different place.

Davies gives effusive praise to the show’s lead.

“He’s ferocious.

He’s a limitless actor,” he says of Gatwa.

“He’s a joy.

He’s a force in the world.

I think we’re doing him proud.”

The new season ofDoctor Whopremieres on BBC and Disney+ on April 12.