Image caption Anneke Wills played Polly from 1966-67 with both William Hartnell and Patrick Troughton's Doctors

Former Doctor Who actress Anneke Wills says Patrick Troughton's "adorable" performance was key to keeping the show going in the 1960s.

Wills played companion Polly to William Hartnell's grandfatherly first Doctor and Patrick Troughton's scruffy second incarnation in 1966-67.

The show's producers decided to "regenerate" the lead role when Hartnell's health declined.

Saturday is the 50th anniversary of The Power of the Daleks, Troughton's debut.

The six-part adventure sees Troughton's time lord, and his Tardis companions, Polly and Ben (Michael Craze), do battle with the evil Daleks on the planet Vulcan.

To mark the anniversary, BBC Worldwide is releasing a black-and-white animated reconstruction of the "lost" story, based on surviving photographs and audio recordings.

Image copyright BBC Store Image caption The Power of the Daleks was first broadcast from 5 November to 10 December 1966

Speaking at a screening of the first two episodes, Wills recalled how various actors - including Michael Hordern - auditioned for the role of the new Doctor.

"We all knew Bill [William Hartnell] was going to leave at the end of the summer season, and then there were discussions about is that the end of the show or shall we have another actor," she said.

"When we heard it was Patrick, we knew that we had a chance.

"But we still didn't know if the audience would accept it and accept that the Doctor could change his body.

"And it was entirely up to Patrick that the audience did.

"In the animation you see how adorable he was, you couldn't resist him. And they didn't resist him.

"So luckily it was him and we're all here talking about it."

In this interview, Anneke Wills talks about about her memories of 1960s Doctor Who and what she think of Peter Capaldi's 12th Doctor.

Image caption Michael Craze (Ben), Anneke Wills (Polly) and Patrick Troughton (The Doctor) filming The Power of the Daleks in 1966

Why is The Power of the Daleks so important in Doctor Who history?

This is the first time ever the Doctor changes his body.

For us at the time, it was a momentous moment.

Were we going to have a Bill Hartnell lookalike? Or someone totally different?

There were all these different names coming up. But also, as an actor, you were thinking: "I hope I'll be in work at the end of the summer break."

How did you find the transition from William Hartnell to Patrick Troughton?

Bill had become very difficult to work with - we had to be very generous and kind and pick up his lines.

The thing about Patrick was that he had no ego. That was an astounding thing.

I think his performance in this story is the most astounding of all the Doctors - and I've watched them all.

What other memories do you have from this story?

We had two weeks of rehearsal so Patrick had extra time to get into the role.

He put on his Harpo Marx curly wig, and Michael Craze said: "If you're going to wear that, I'm not bloody working with you," and went off for a smoke.

I was worried we were wasting time, so I took a comb out of someone's pocket and combed his hair forward in a Beatles style and messed it up a bit.

There was a silence as Patrick looked in the mirror.

And then he said: "I like it."

Ninety-seven Doctor Who episodes are still missing. How do you feel about them being junked?

We did that in those days. We never saw any of the work that we'd done. It was like rep theatre. You'd do a wonderful performance and then it's gone.

Now, looking back, it seems a terrible waste.

I love that Polly and Ben have been brought back [in animated form] because there's so little of us that survives.

What would you like to see animated next?

I would love it if they would do The Smugglers [a swashbuckling Hartnell story from 1966], next I'd love to see The Crusade [an earlier first Doctor adventure starring Julian Glover as Richard the Lionheart], and Fury of the Deep [a second Doctor sea-monster story from 1968].

Do you think any more 60s episodes will turn up?

Wouldn't it be wonderful? I don't know any more than the fans. They always think that I've got secrets, but I haven't .

If anybody's got one in their cupboard bring it forth - now is the moment.

Someone should make a spy thriller about the search for the missing episodes of Doctor Who.

How much has role of companion changed over the past 50 years?

Polly was created as a proactive young woman and, in a way, that hasn't changed. However, I take exception when the companion slaps the Doctor. That makes me really angry.

How much would you like Polly to return to the TV series?

That scares me to bits. All these wrinkles in high definition? I don't think so.

I talked to Peter Capaldi. I think he's astounding. He's luminous.

He asked me if there was a lot of pressure in the 1960s and I said we'd start rehearsals on a Monday, and he said: "You rehearse?"

But if they asked, would you do it?

Yes. Of course I'd take on the challenge. Maybe I could be in a wonderful mask.

The Power of the Daleks will be available on Saturday 5 November at 17:50 GMT on BBC Store, 50 years to the minute after it was first broadcast in 1966.

The first three minutes of episode one will also be streamed globally on Twitter.

Follow us on Twitter @BBCNewsEnts, on Instagram at bbcnewsents, or if you have a story suggestion email entertainment.news@bbc.co.uk.