The War Between the Land and the Sea has sacrificed one key character - and here's why it's the right call

Warning: Major spoilers ahead for The War Between the Land and the Sea episode 3.

In mere moments, The War Between the Land and the Sea has changed everything for one Doctor Who character - and, while it may be a heartbreaking watch, it was definitely the right call.

So far, the Doctor Who spin-off has massively proven its worth by finally developing the character of Kate Lethbridge-Stewart, and the devastating events of episode 3 have amped this up in a big way.

First portrayed by Beverley Cressman, Kate was reimagined by Chris Chibnall in the 2012 episode The Power of Three, being played by Jemma Redgrave, and she's remained a constant in the Whoniverse ever since, becoming the commander-in-chief of UNIT. But, in those 13 years, what have we actually learnt about Kate?

Despite her longevity in the Whoniverse, Kate is one of the most underdeveloped major characters, with audiences knowing little to nothing about her life outside of being UNIT's commander-in-chief and the daughter carrying on the legacy of Nicholas Courtney's Brigadier.

As Redgrave herself alluded to in a recent interview with RadioTimes.com, the most we ever really learn about Kate's backstory is a passing mention of her being a divorcee and an "outstanding bridge player" in the episode Death in Heaven. For a character that's been around for over a decade, it's not exactly much to go on.

It's not hard to see why Kate has often been sidelined in the main show - seasons of Doctor Who are incredibly time-limited and the priority must be developing the relationship between the Doctor and the companion, not the ins and outs of UNIT's personnel. But to finally see such a long-serving figure get her time to shine is a huge relief - even if it is at the expense of another character.

While not everyone loved romance between Kate and Colonel Christofer Ibrahim (Alexander Devrient), being confirmed in episodes 1 and 2, it showed us a different side of UNIT's commander-in-chief - a woman conflicted about how how her relationship and her work can co-exist, not to mention the issue of the age difference and the power dynamic which she was clearly grappling with.

We see even more of Kate in episode 3, after war is declared. This time, she's at her limit, exhausted and battle-weary, yet refusing to rest despite her sleep deprivation as Barclay (Russell Tovey) and co descended to the ocean floor on their diplomatic mission. Notably, it's only an intervention from Christofer that gets her to return home and rest, as he shows deep concern for her.

But, after that relationship was built up, it's been swiftly ripped away with Christofer's sudden and tragic death at the hands of the assassin, who was aiming to kill Kate herself. It's the most significant death in the Whoniverse for quite some time, driving home just how much danger the world is in in the new spin-off.

After Kate was sidelined for so long in Doctor Who, I felt that she deserved more in The War Between than just giving her a home life. But sacrificing Christofer? That has set the stage for an interesting internal conflict for Kate, who somehow has to help humanity through a world-threatening crisis while clearly spiralling after a deeply painful personal loss. And that is certainly something to work with.

She also has to manage the destructive wills of the world leaders around her, while grappling with her survivor's guilt, knowing that that bullet was meant for her, and the trauma of seeing the man she loves - seemingly the only person who could get through to her - die in her arms. Presumably, we're now set to see her torn between what's right for humanity, and her personal vengeance.

Already, in the wake of Christofer's death, Redgrave has been able to show so much more range as an actress in a way that completely outshines what she's been working with before, and I'm excited to see that continue.

For more than a decade, Kate's main role in Doctor Who has been carrying the legacy of the Brigadier. Now, finally, we get to see her shine on her own. That, for me, is worth the sacrifice of another character - and worth the wait.

The War Between the Land and the Sea will end on Sunday 21st December. Doctor Who is available to watch on BBC iPlayer.

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