Doctor Who legend Carole Ann Ford reveals that she and her co-star, William Hartnell, gave their characters backstories because the BBC never did. Ford played the Doctor's first companion, Susan Foreman, in the very first episode of Doctor Who, "An Unearthly Child," in 1963, before the two parted ways in 1964. Based on her backstory, it aligns with what was shown in a 2013 episode.
In an interview with RadioTimes, Ford reveals that she and Hartnell collaborated to give their characters a backstory and a reason for their decision to travel. She shares that the TARDIS model that they stole was a "previous model" that wasn't "working smoothly" as they should have. With the Doctor being a tinkerer, he did some work to get it running. From there, he just brought her to the TARDIS and off they went, until they landed at Totter's Lane. Here's Ford's explanation:
"We thought that the most likely thing was that the TARDIS was not this yea's model. It was a previous model which had been tarted up a bit, and the tarted up bits weren't quite working as smoothly as they should have done. So Bill, my grandfather, was in a huge sort of aircraft hangar-type place with loads and loads and loads of other TARDISes, all being tinkered with. And he was tinkering away with it and making everything work more smoothly, when suddenly there was an invasion from another planet. Everybody was going crazy, and he just bundled me into the TARDIS and said, 'Right, we'e out of here.' So we got in with only a partially-working TARDIS, which he continued to fiddle with throughout the series, and finished up where we finished up – Totter's Lane."
Foreman's backstory is almost similar to what was shown in the Doctor Who season 7 Episode, "The Name of the Doctor," where it revealed that back in Gallifrey, The Doctor and Susan went to steal a faulty TARDIS so they can travel across time and space, only for Clara (Jenna Coleman) to recommend a different TARDIS with broken navigation system that the Doctor would most likely have fun with.
Who is Susan Foreman in Doctor Who?
Ford starred in Doctor Who in 1963, appearing in 52 episodes and a handful of specials. She played Susan Foreman, the Doctor's granddaughter, who studied at Coal Hill School. One day, her teachers, Barbara Wright (Jacqueline Hill) and Ian Chesterton (William Russel), noticed that Susan's knowledge of history and science surpassed that of her peers. So, after getting her address, they found out that she was living in a junkyard, only to find out that she lives in a TARDIS, disguised as a police box.
Susan's last major Doctor Who appearance was in the 1964 episode "The Dalek Invasion of Earth," where Susan falls in love with David Campbell (Peter Fraser), a freedom fighter in the 22nd Century. Susan was locked out of the TARDIS, only for the Doctor to tell her that he would see her again.
When Doctor Who returned in 2005, Susan was referenced a handful of times by the modern incarnations of the Doctor. Her most recent appearance was during the show's fifteenth season, where she appeared in a series of visions the Doctor had during the episode "The Interstellar Song Contest," and returned once more in Season 15's penultimate episode "Wish World."
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