Doctor Who ex-boss Steven Moffat finally answers a big question about Heaven Sent

The latest watchalong - organised by Doctor Who Magazine writer Emily Cook - was for the acclaimed 2015 episode Heaven Sent and saw Moffat answer fan questions, including one which has been bugging Whovians ever since original broadcast.

Heaven Sent sees the Doctor trapped in a Gallifreyan confession dial, with the following episode establishing that he was locked inside for over 4-and-a-half billion years. So does this mean the Doctor is now billions of years old?

Moffat doesn't think so, explaining that since Heaven Sent involves the Doctor repeatedly being mortally wounded and "resetting" his body using a teleportation chamber, all those years spent in the dial don't add to our hero's physical age.

"[It's] up to you," he wrote, responding to a fan query about whether the Doctor aged. "I think not, though - he keeps resetting."

As for the suggestion that the resetting process means that the original Doctor died in Heaven Sent and the one we've been following ever since is a carbon copy, Moffat provided some less-than-comforting insights...

"He first teleported in [1964 story] The Keys of Marinus – he's been a copy since then – deal with it, kid," he joked.

Of course, since the entire episode took place in the confessional dial and we don't know exactly how that piece of Time Lord tech works, it's possible that only the Doctor's consciousness was trapped inside and that his physical form wasn't affected by any of the events that happened therein...

Whatever you might think, it says something that we're still unpicking and dissecting Heaven Sent five years later – and will no doubt continue to do so for years to come.

The next Doctor Who watchalong will be for 2008 two-parter The Stolen Earth / Journey's End, with Russell T Davies and director Graeme Harper joining the tweetalong along with our guests yet to be announced.

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