Doctor Who favourite Alex Kingston thinks David Tennant started to "disengage" from the role ahead of his emotional exit

It’s hard to think of an actor more enthusiastic about Doctor Who than Tenth Doctor star David Tennant.

In fact, Tennant, a fan since childhood, is so passionate he has returned to the series twice – first in 2013 for the show’s 50th anniversary, and then again for the 60th in 2023, in which he played a new incarnation of the Time Lord, the Fourteenth Doctor.

Despite – or perhaps because of – this, River Song star Alex Kingston has now said that when she starred opposite Tennant in season 4 story Silence in the Library/Forest of the Dead, the actor was already starting to “disengage” from the role as he approached the end of his initial tenure.

The story in question was Kingston’s first as River Song, and aired in 2008, as part of Tennant’s last full season. He would go on to star in a series of specials the following year, before his regeneration was broadcast on New Year’s Day 2010.

Speaking with the Oxford Mail, Kingston was asked whether she knew she was going to be in the role of River for a long time at that point.

Referencing Tennant’s then-impending departure, Kingston said: “I didn’t know, but I think that the announcement had either just happened or it was about to happen while we were filming.

“People knew that was going to be David’s last season, so there was just an element, it wasn’t melancholy, but there was just an energy that I was aware that somehow something had shifted. I don’t think he ever wanted to stop playing the Doctor, as he loved it so much.

“It wasn’t that he didn’t welcome me because he absolutely did, but I think it was him starting to already disengage with the character. I’m not even sure whether he knew he was doing that consciously or not, but there was just something there.

“Whereas with Matt [Smith], he was about to start, and was looking for that support to help him step into David’s very huge shoes, enormous feet!”

Kingston went on to appear opposite Smith’s Eleventh Doctor in multiple episodes across all three of his seasons (season 5, 6 and 7), before reprising her role for one episode during Peter Capaldi’s tenure.

That episode, 2015 Christmas special The Husbands of River Song, is the final time she has appeared in the series on screen to date, although she has reprised her role as River for multiple Big Finish audio dramas, including an upcoming story with Arthur Darvill’s Rory.

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