Doctor Who writer Steven Moffat has revealed which episode he thinks is the “median average” of his era.

Moffat will step down as Doctor Who showrunner at the end of 2017 after eight years in the role, with Broadchurch creator Chris Chibnall taking over for 2018’s season.

Asked by Doctor Who Magazine in Issue 502 (out now) which story would be his era’s “most reliably average episode” – the median if he were to rank every episode that he has overseen, from his favourite to his least favourite – Moffat answered: “Well, I’ll have to choose one that I wrote, otherwise I’m going to upset somebody … I went back and watched it again, and I thought ‘no, actually, it is quite good,’ but it is resolutely sort of middle, I think, and that’s ‘The Bells of St John’.”

‘The Bells of St John’ aired in March 2013 and launched the second half of Matt Smith’s final season, introducing Jenna Coleman as Clara following two previous appearances as what were later revealed to be splinters of her character scattered through time.

Moffat explained: “It’s got a fairly inventive monster. It’s got some great action scenes, like the bit on the plane. There’s the pretty good scene where the Doctor is underneath Clara’s window. Some good gags. Lovely music. But I don’t think that episode will change anybody’s life.”

He added: “It’s a very well-carpentered bit of telly, and it’s – that underrated thing – a very good first episode. Sort of. First episodes are rarely winners, but they are very difficult to do.”

Moffat recently described making Season 7 as “a tough, time time” and “a bit miserable,” saying: “I didn’t enjoy my third year as much.”

The new season of Doctor Who began filming in Cardiff in June and will air on BBC One in spring 2017.

Here’s everything we know so far about Season 10.

What did you think of ‘The Bells of St John’? Let us know below…