Doctor Who explains key character absence in Lucky Day

Though we were reunited with Kate Stewart (Jemma Redgrave), her right-hand man Colonel Ibrahim (Alexander Devrient) and scientific advisor Shirley Anne Bingham (Ruth Madeley), Mel Bush (Bonnie Langford) was missing from the line-up.

Mel originally appeared on Doctor Who as a companion between 1986 and 1987, returning for a brief cameo in 2022 before appearing in a recurring role in last year's episodes.

Her most recent outings revealed that she had been recruited by international military organisation UNIT and saw her battle fantastical threats alongside first the Fourteenth Doctor (David Tennant) and later the Fifteenth (Ncuti Gatwa).

New episode Lucky Day sees another former companion, Ruby Sunday (Millie Gibson), reach out to UNIT for reassurance when her trip to an apparently quaint English village is disturbed by suspicious electrical anomalies.

Ruby attempts to contact Mel, but her call is intercepted by Kate instead, who explains that Mel is out of the country.

"Mel’s on her way to Sydney," says Kate. "There’s something strange happening in the harbour."

That's the last we hear of Mel's assignment, but it's apparently serious enough that she doesn't subsequently return to the UK when UNIT is targeted by Conrad Clark (Jonah Hauer-King), a devious con man who uses his digital platforms to amplify dangerous conspiracy theories for financial gain.

With reference to "something strange happening in the harbour" – and so presumably a possible threat emerging from the water – might we possibly learn more about what Mel was investigating in upcoming Doctor Who spin-off The War Between the Land and the Sea?

There's also no sign of either UNIT's other scientific advisor Morris Gibbons (Lenny Rush) or their latest recruit Rose Noble (Yasmin Finney) in Lucky Day – though perhaps with UNIT under investigation in the episode, that's just as well, or else Kate Stewart might have found herself in hot water over flouting child labour laws...

Read more:

• Doctor Who's Lucky Day resolves one major series mystery
• Doctor Who sees iconic character return for unexpected cameo in Lucky Day

Doctor Who continues next Saturday (10th May) on BBC One, with new episodes available from 8am on Saturdays on BBC iPlayer in the UK. The series is available on Disney+ outside of the UK.

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