Katy Manning breaks down her heartbreaking Doctor Who exit

However, she still looks back with great fondness on her official, original final story, as the actress discussed exclusively with RadioTimes.com.

"What was fascinating is that really, in life, so often you can overplay emotional scenes," Manning said. "You can overplay those exits. No words when necessary.

"And it's just as well, because there wasn't a dry eye in that studio. The only person that was so joyously happy was Stewart Bevan!"

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Manning explained: "But it was so touching because, when you look at it - and I don't watch things from the past, to be honest with you - but when I've seen that, I actually still feel the emotion, even talking about it.

"Because I keep everybody that I've ever loved in my life, who's gone, I keep them all with me, I don't do all that completion.

"And so, when they start to talk about them, I suddenly get the feeling of how much they meant to me. And then I get a bit emotional."

She continued: "But it was so beautifully written. And what was so clever about that, and a lot of people when I tell them, they go, 'Oh, yes, I hadn't thought about that,' but Jo destroys Cliff's experiment.

"He calls her a little goat, and get out of my way, and the Doctor had called me something about a bun vendor because he thought I was a tea lady.

"So both of them found Jo a little bit irritating to begin with, because she was trying to be so desperately helpful. As I say, you've always got to be very suspicious, when people go, 'I'll do it, I'll do it!'

"And she ruined his experiment by knocking over the thing on to his mushroom spores and all that kind of thing. And it was lovely.

"So it was like, she found this person, that was the closest thing that she could ever find, because she did have this enormous love for the Doctor, but she finally found the man that she could continue her life with. And it started in exactly the same way as her first meeting with the Doctor, which I thought was really beautiful writing.

"And also, for me, having been the mad hippie, as everybody used to call us, who talked about the planet and the dangers that we were bringing to this planet by living the way that we live, which was going on in the '60s, Barry Letts was also very concerned about all this. So it was a wonderful one to be involved with."

Earlier this year, Manning revealed that she "knows" that "there will be people returning" for new Doctor Who spin-offs, but didn't confirm whether she would be involved in any of them.

However, she did say that it would be "lovely if [Jo] just occasionally comes in for a very good reason".

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