It's less than 12 hours until this year's Christmas special airs on BBC One in the annual Doctor Who tradition. The Doctor finds himself in yet another adventure with River Song but this time she has no idea who he is.

Please note: This review contains minor spoilers and hints to something that is slightly more than minor (which you need to highlight to read).

After a really dark few years, from the crying at Matt's departure in Time of the Doctor to the rather depressing Last Christmas to... well... series 9, Steven Moffat brings us some much needed light entertainment with a touch of melodrama in this year's Christmas special With the exception of the final 15 minutes, that's really all this episode is.

Returning this year is Doctor Professor River Song much to the love hatred of a lot of people, to the point of the episode being judged far too early. This is most definitely a mistake as I found her character to be very enjoyable, especially as it's fantastic to see River Song's behaviour without the Doctor (I'm actually much more looking forward to her Big Finish audios now).

It's clear from Alex Kingston's performance that she immensely enjoys playing her character, including a rather smutty action that many a middle-aged man would have thought of more than once. Sadly though, if you don't enjoy River Song, you probably won't enjoy the episode all that much.

The episode sees multiple role reversals. Our primary one is how River doesn't know who the strange man is, and does so in a way that, once again, cheekily ignores Moffat's own setup of the opposite personal timelines. It works pretty damn well though and only compliments River's character overall.

In turn, The Doctor (as some 'clever doctor guy') gets his chance to take on the companion role light-heartedly, something that'll be much to the delight of many fans. While it's clear that some time has past since Hell Bent, and The Doctor is still recovering from the loss of Clara, Moffat manages to find a great compromise between needing some fun Christmas time and not pretending it never happened, although the lack of any mention is a little surprising.

You can tell that Peter Capaldi had great fun making the episode and his chemistry with Alex Kingston might make you wonder if this isn't really their first episode together.

There are, however, just a few minor gripes with this episode. One is just how long River doesn't know it's him. While it's still somewhat enjoyable, it does get rather battered about a bit, although the fact that it is lampshaded is good to note. As a result, a lot of the character chemistry is left squashed towards the end as opposed to being a little more spread out.

While it works very well as a standalone episode for those who haven't seen anything pre-Capaldi, there's an awful lot of references to past adventures that will fly over the heads of a lot of viewers, and may not add the required depth to the episode. For example, the episode assumes viewers know River Song's storyline, something that hasn't been touched upon since 2013.

Having said that, the references it does make work very well and align up more perfectly than you may realise on first watch, such as making the timeline clearer, solving a certain minisode conflict  (highlight to read) and pictures of The Doctor (Hartnell and Troughton are in colour instead of black and white, something that has been a pedantic gripe of mine for a while).

While the guest cast won't be winning any rewards, Greg Davies, as King Hydroflax and Matt Lucas and Phillip Rhys as River's 'partners' in crime perform adequately in their roles, although are rather underutilised. King Hydroflax is silly, stupid and over-the-top. If this was at any other time of year, that'd probably ruin the episode for me. But again, it's part of what the episode is aiming for at an appropriate time and audience. Nardole "works", but the humour he's featured with falls flat more than once and his character feels little more than just being added to the episode because Lucas wanted in.

Douglas Mackinnon, most previously known from Listen and Time Heist, returns as the director of the episode, providing excellent style and gorgeous and especially warm shots. Murray Gold's music has some nice callbacks and is wonderful to listen to, not that you have much of a choice.(unless our preview video was bad, there'll be more than one audio mixing complaint made!).

It's neither the best episode of late nor is it some game-changing featurette with immense revelations, or anything that is very in-depth, but it sets the expectations of a good fun romp well and hits them on every note. The biggest downside is that it is rather expectant that viewers will be dragged along with it if they don't like that sort of thing. Definitely one of the better Christmas specials. IMHO 8/10.