Doctor Who fans theorise new pic reveals return of the Sontarans

When returning showrunner Russell T Davies shared the still on his Instagram account, he included a potato emoji alongside the now traditional two hearts and addition sign, and this has led to a new theory emerging about a possible return for the Sontarans.

The classic aliens – who were first introduced in the 11th run of the classic series and last appeared in the season 13 finale The Vanquishers – have previously been described as "huge potatoes with ray guns".

And this has not been lost on some viewers, with one fan writing: "Probably means it’s a Sontaran episode. There’s really nothing else a potato could mean for Doctor Who."

"I've seen a few people on the timeline suggest Sontarans," added one Whovian, while another commented: "I wouldn't mind seeing the Sontarans return for this series, to be honest."

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But that's far from the only theory that has been put forward by fans: some reckon that the potato is instead a clue to some historical context for the episode, given the characters are dressed in period garb.

For example, many viewers have put forward a suggestion that it could mean Groff is playing legendary composer Wolfgang Amadeus Mozart, given there is a type of potato that shares a name with the famed musician.

However, the unofficial Twitter account Doctor Who Production News pointed out: "He doesn’t look anything like any of the portraits of Mozart I googled... Maybe the potato is a red herring."

Red herring or not, the clue will certainly keep fans guessing for the foreseeable future...

Groff previously said of joining the BBC sci-fi series: "I am so thrilled to jump into the extraordinary mind of Russell T Davies and watch the incredible Ncuti Gatwa soar in this iconic role!"

Doctor Who is available to stream on BBC iPlayer with episodes of the classic series also available on BritBox – you can sign up for a 7-day free trial here.

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