Doctor Who leaves door open for Susan Foreman return with emotional finale

Ever since a reference to Susan – who appeared on the show from 1963-64 – was included in this year's The Devil's Chord, fans have been hoping that the character might reappear on-screen.

There was even speculation that the mysterious character played by Susan Twist, who has appeared across time and space in various different guises, could be the Doctor's long-lost granddaughter.

In last week's episode, The Legend of Ruby Sunday, the Doctor himself even begins to suspect this might be the case – with Twist's latest alter-ego, tech entrepreneur Susan Triad, sharing a first name with his grandchild.

Eventually, however, Susan Triad was revealed to be something else entirely – a harbinger of the god-like being Sutekh, who almost destroyed the universe with his devastating dust of death.

Despite this, the original Susan does make a cameo of sorts in latest episode Empire of Death, with archive footage of the character appearing briefly as Sutekh explains the inspiration behind his trap for the Doctor...

Having invaded the TARDIS, Sutekh was exposed to all of the ship’s "secrets" – including memories of Susan. Inspired, the Osiran "created an apparition of her, universally" – a woman who resembled Susan was brought into existence anywhere the TARDIS landed, with the combined might of Sutekh’s power and the TARDIS’s perception filter enabling the woman’s various guises to be birthed as real beings who fitted into history.

The real Susan is also referenced towards the end of the episode, with the Doctor suggesting that he might still go looking for his granddaughter.

Bidding an emotional farewell to companion Ruby (Millie Gibson) after she was reunited with her birth mother, the Doctor insists he will see his friend again one day. "Your own granddaughter… you left her and never went back," Ruby reminds him. "And that was my mistake," he replies. "Maybe I’ll find her again, one day."

His experiences with Ruby – who was so desperate to be reunited with her biological parents – have reignited in the Doctor a yearning for family. "You changed me," he says. "I talk about family in a way that I never did before – it’s because of you."

When he left Susan behind on a future Earth in 1964's The Dalek Invasion of Earth, the First Doctor (William Hartnell) swore that "one day, I will come back" – so will we see the real Susan again?

Back in The Devil's Chord, the Doctor suggested that the genocide that wiped out the Time Lords might have killed her – but speaking exclusively to RadioTimes.com back in May, original Susan actress Carole Ann Ford refused to rule out returning to Doctor Who.

"As we know, with Doctor Who, absolutely anything and everything is possible," she said. "The mind boggles with all the many ways Susan could come back, where and when. But I think she would love reuniting with her grandfather in his new form. Isn't Ncuti [Gatwa] amazing!"

Read more:

• Doctor Who finale sees Millie Gibson's Ruby depart the TARDIS in emotional scenes
• Doctor Who reveals identity of Ruby Sunday’s mother after season-long mystery

Doctor Who will return to BBC One this Christmas. Previous seasons are available to stream on BBC iPlayer.

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