I'd call that the most consistently entertaining episode of the 13th Doc's run thus far. Worked on pretty much every level. Particular credit to Segun Akinola for a wonderfully varied score (personal highlight: a lovely Barry homage as the villain's palatial home is established), the new aliens for actually being unnerving and threatening, Stephen Fry for being game enough to die so soon into the episode, Lenny Henry just for being Lenny Henry, and finally Sacha Dhawan, given a killer reveal and playing it to the hilt.
Oh, that reveal. The cherry on top. I've always wondered what it was like not to know a Big Name Villain is returning, and now I can say...it's great! Fabulous extra punch to propel us into a strong, strong cliffhanger. Yes, a lot rides on the second ep, on making the landing, but the journey to date has been huge fun. If this is a taste of what's to come...oh, myyyy...