Millie Gibson's future on Doctor Who is still very bright

It's definitely a strange situation, to have only seen our brilliant new companion Ruby Sunday in one episode before it's revealed when and how she'll be stepping back (not stepping down – there's a big difference). But it certainly doesn't have to be a bad thing – in fact, I think this could be a huge storytelling opportunity and a big chance for Doctor Who to evolve its relationship with its companions.

There's a lot we don't know for sure how Gibson's storyline on Doctor Who will play out but what we do know actually sounds pretty great to me. Presumably, with Gibson still appearing in season 15, we'll be able to see how Ruby's journey continues after her adventures with the Doctor – and what a rare and wonderful thing that could be.

We as viewers have an intense and complicated relationship with Doctor Who companions. While the Doctor, by invention, is an unknowable being, the companions are the opposite for us – they're our eyes and ears. From the time they meet the Doctor and take their first steps into the TARDIS with an inevitable: "It's... bigger on the inside?!", to them eventually leaving their adventures behind, they're our representative on this strange and wonderful journey.

But, so many times over the years, companions have left the TARDIS and that's been the very last we've ever heard from them. Lest we forget when Susan (Carole Ann Ford), the first ever companion, was literally locked out of the TARDIS by her grandfather (nope, I'm still not over it).

Sure, that's the nature of the show sometimes, but the times we've been able to check back in with the companions have been incredible – from Freema Agyeman's return as badass Martha Jones in season 4 to Catherine Tate's incredible Donna Noble starring in the 60th anniversary specials, to Bonnie Langford's Melanie Bush making her return as a fully fledged companion in season 14 – and getting to do a lot more than ever before.

Something else we know for sure about Gibson stepping back after one season is that this is nothing really out of the ordinary. It might seem a bit odd and quick to already know about how Gibson's role will change because of how far in advance the show is filming (the 2025 season is currently in production) but plenty of companions have only stayed as the main companion for one season – and have absolutely smashed it along the way.

Take Agyeman for example – she had a ridiculously difficult job in following Billie Piper as Rose Tyler (RTD's only two-season companion) but quickly proved why she was the right actress for the job. By the end of her season, Agyeman had made Martha a force to be reckoned with and an undeniably important part of the show's history, well justifying a return for her in season 4.

Then there's Tate – another one-season companion who became so well-loved that she joined David Tennant for three 60th anniversary specials that ushered Doctor Who into a new era. One-season companions are no less important or worth investing in than those who stay for longer. Their stories are just as impactful, just as exciting and stay with us for just as long as those who might have had a two or three-season run.

Plus, Doctor Who, by design, is all about change – from the moment William Hartnell regenerated into Patrick Troughton to the spell-binding bi-generation late last year. More than any other show in the universe, it relies on new actors coming in and changing things up, and it's absolutely thrilling.

The casting of the brilliant Varada Sethu does nothing to take away from Gibson's role or performance. Her casting certainly doesn't automatically mean Gibson has been "dropped" or "axed" or that the two actresses should be pitted against each other. Surely we can appreciate the work of two wonderful actresses and be excited about seeing them smash it during the same season?

Because, honestly, there's so much to be excited about right now as a Doctor Who fan.

I'm excited to see Sethu in action. She's already more than proven her acting chops in Andor and various BBC dramas and it'll be amazing to see what's in store for her.

I'm excited to see what the future holds for Gibson. At the age of 19, she's secured roles on Coronation Street and Doctor Who, two incredible British institutions. She may well follow in the footsteps of Karen Gillan, Hollywood icon, or Jenna Coleman, staple of British drama – or, more likely, forge her own path. There's no doubting there are incredible things ahead of her.

I'm excited that my favourite show is highlighting the talents of two incredible actresses – and I hope we get to see their characters interact in some way. But, more than anything, I'm excited to be taken along for the ride. I think it's going to be something special.

Doctor Who will return in May. Check out more of our Sci-Fi coverage or visit our TV Guide and Streaming Guide to find out what's on.

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