Doctor Who's Caroline John thought she "wasn't very good" on the show – until fans changed her mind

Speaking at a screening of her mother's first story Spearhead from Space at the BFI Southbank, John's daughter Daisy Ashford explained how the manner of John's departure from Doctor Who initially impacted her feelings towards the series.

"I think she left under a bit of a cloud," Ashford said. "The story goes that they didn't like the fact that her character knew so much, was so intelligent – they were looking for someone that could better ask the Doctor, 'What's going on?' – so she left thinking she wasn't very good on it and sort of left it behind."

The character of Liz was written out off-screen between Doctor Who's seventh and eighth seasons, with producer Barry Letts and script editor Terrance Dicks feeling the character's high intelligence and scientific background meant she couldn't function effectively as an audience surrogate.

In 1978, John herself admitted that she role the role "restricting", explaining that she was "excited at first to be a brainy girl, but all the directors wanted really was a sexy piece."

It was her experience meeting fans of her character at Doctor Who conventions in the years that followed which helped improve her relationship with the series, Ashford said.

"It wasn't until years later – she'd been asked and asked if she'd go to conventions and she finally went to one in Manchester. She got a standing ovation and was like, 'Oh wow, these people actually like what I did!' and then was invited back into the family again.

"She really cherished that and she loved meeting the fans. So it wasn't a big part of her life in the beginning but once she came back into the fold, it meant an awful lot to her."

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Ashford now plays Liz Shaw herself, taking up John's former role in audio plays from Big Finish – calling the opportunity "a gift" from her late mother, who passed away in 2012.

"I felt very lucky – it felt like a real privilege to be offered that, because I know how much it means... and it's something I share with her, so that's really lovely."

Far from being a problem to write around, Liz's character is now able to be explored in all its fullness, she suggested.

"Liz was a bit of a trailblazer for women in the '70s. She knew her own mind and she obviously had to defer to men somewhat, but she didn't do it willingly!

"The writers at Big Finish have done a brilliant job of exploring that side of her. Anything I can do to explore those sides of her that didn't get as much of a chance to come out back in those days, I think that's extraordinary."

Doctor Who: The Collection Season 7 – starring Jon Pertwee, Caroline John and Nicholas Courtney – will be released on 3rd March.

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