Doctor Who fandom went wild back in September when Sophie Aldred unexpectedly reprised her role of companion Ace, 30 years after she was a regular on the BBC sci-fi series.

A specially-shot trailer for Doctor Who: Season 26 – The Collection Blu-ray set saw Aldred play an older Ace – a teenager when she first appeared, the character was head of a philanthropic foundation called A Charitable Earth.

Ace’s fate was left in limbo when Doctor Who was originally cancelled in 1989, but the notion of A Charitable Earth (A.C.E. – geddit?) was first introduced by Russell T Davies in spin-off show The Sarah Jane Adventures.

Speaking at a BFI screening to mark the release of the Blu-ray set, Aldred revealed that she initially had some trouble imagining her tough, no-nonsense character taking up the path that Davies had suggested.

“When I first heard about A Charitable Earth, I thought, ‘Huh? Ace working for a charity?’

“And then I thought, ‘No, hang on a minute…’ because of her experience and the fact that Ace has… she has got a real heart… she wants to do right, I could see her heading up a corporation called A Charitable Earth. I thought that was just right.”

The ‘Ace Returns’ trailer was scripted by writer Pete McTighe, who also wrote the episode ‘Kerblam!‘ for Jodie Whittaker’s first Doctor Who series and will return to write another adventure for the upcoming series 12.

“I can think of no better tribute and celebration [of Ace] than Pete’s fantastic trailer,” Aldred said.

“I was just so thrilled when Pete sent through the script – in fact, I was so thrilled that I burst into tears, because it was really emotional.”

With a fan in the audience suggesting that the trail was the perfect set-up for a spin-off, Aldred responded, “Yes, isn’t it just? Let’s do it!”

Ace’s ultimate canonical fate is quite different to what had originally been intended for the character had Doctor Who continued into the ’90s – with the original intention being to write her out by having the teenager take up residency on the Doctor’s home planet of Gallifrey.

“There probably would’ve been a handover to a new companion in the course of that [next] season,” explained Andrew Cartmel, who served as script editor on classic Doctor Who’s final three seasons.

“[Writers] Marc Platt and Ben Aaronovitch had got together and they’d cooked up this great exit plan for Ace where she goes to the Prydonian Academy… and becomes like a Time Lord.

“Ace was such a fab companion, we couldn’t just let her disappear.”

Aldred added:

“I didn’t know [that plan] at the time, but what a great thing that would be!”