Russell T Davies' finales are often among the most epic. Stories like Utopia/The Sound Of Drums/Last Of The Time Lords and The Stolen Earth/Journey's End do an excellent job at raising the excitement levels before the plot is resolved. The Legend Of Ruby Sunday is the first part of this year's two-part finale, and it's more of a slow burner until the last five minutes. The Legend Of Ruby Sunday leaves you with far more questions than answers. Before going in, I was anticipating a reveal of who Ruby's biological Mum would be, for instance, as RTD including A Good Man Goes To War as an episode to watch in preparation for this one made me think the cliffhanger would be a familiar face revealed to be Ruby's mother. Instead, who her Mum is becomes more mysterious than it was before, as all we see is a hooded figure pointing northwest. This isn't necessarily a bad thing, as it makes it all the more fascinating a mystery, but it does mean that next week's episode has more to resolve (and the cliffhanger definitely seems to suggest we'll see who Ruby's Mum is next week).

There's some really lovely character moments in this one, particularly in relation to the Doctor's granddaughter. Kate's heart-to-heart with the Doctor over Susan Foreman, and whether he wants to see her, is easily the best scene Kate has ever had, as it gives her more personality than she has received in her other appearances. She has this real maternal quality to her when speaking to the Doctor about Susan that makes me wonder if she might be Ruby's Mum.

I also like the concept of UNIT's time window, which is very similar to The Girl In The Fireplace, although doesn't seem to be the same as that story's time windows. It's a brilliant idea to suggest that UNIT would have this kind of technology on hand, and makes sense that the organization would utilise it to view past times for their operations. Less convincing is the idea that UNIT would hire kids to work for them. Having 13 year olds like Morris working as scientific advisors suggests a morally grey side to UNIT that's not explored in the episode. They're essentially throwing 13 year olds into hugely dangerous extraterrestrial and supernatural situations, which seems a little problematic. It would probably have been better to have made Morris an alien, as it would have avoided the more ethically questionable side of kids working for UNIT. He could have just been an adult alien who looks like human child.

The Legend Of Ruby Sunday's highlight is undoubtedly the cliffhanger, which is suitably epic. It's a masterclass of building the tension and hinting at the absolute power that Sutekh holds, and harks back to past RTD cliffhangers like the YANA reveal in Utopia. Although I find Pyramids Of Mars a little overrated, I already find Sutekh much more superior to how he appears in Pyramids Of Mars. In those five minutes alone, he does a lot more to establish himself as a significant threat, possessing people, turning them to sand, and having already taken over the TARDIS. The moment where Susan Triad turns demonic and taunts the Doctor over how he thought she was his granddaughter is so chilling.

Mel gets quite a bit to do in this episode, and it's great seeing Bonnie Langford getting stronger material than she did in the 80s. It's much more enjoyable seeing a Mel who doesn't scream, and instead throws herself into action, as a spy for UNIT. It's also nice to see the return of Rose Noble too, who works well alongside 15 and Ruby. Hopefully Rose's inclusion means we may get to see Donna Noble come back sooner rather than later.

Overall, I would give The Legend Of Ruby Sunday a solid 8/10. It's a bit of a slow burner, and UNIT hiring children doesn't make a ton of sense, but those last five minutes are magnificent, and reflect Russell T Davies's knack for producing excellent cliffhangers. The constant references to Susan definitely make me believe we will see her return before long also, as it would seem a little strange for the Doctor to not return to his granddaughter again after spending so long talking about her to Ruby and Kate.