Now this is how you open a two-parter.

We begin with a great premise and a great setting. The idea of an 'Impossible Planet' that is somehow able to remain suspended above a Black Hole is immediately intriguing, and the threat from the Black Hole is very quickly established to be dangerous, so we're already beginning with some tension. Add to this the untranslatable language (adding to the intrigue) and the loss of the TARDIS (adding to the tension) and we're off to a great start.

Then we have a collection of creepy scenes with strange happenings, all seemingly revolving around an awakening Beast. We also have a likeable supporting cast of well drawn characters, and of course the Ood. What a great design the Ood have. They're strikingly alien, but somehow, despite having a face with limited movement, they're also remarkably expressive. They're genuinely scary when they need to look scary, but when they aren't they seem incredibly sweet. There's a reason they became on of Nu-Who's most iconic aliens. So we have a compelling middle here too.

This all builds to one of the best cliffhangers of the modern era. The Doctor and Ida are down the hole staring at the seal. Toby has infected the Ood who are beginning their rampage on the sanctuary base, killing nameless security dude #1 in their wake. As our heroes are being attacked up top, the seal to the pit opens before The Doctor and Gabriel Woolf's amazing voice tells us that the pit is open and he is free. Now we've got a thrilling end to the episode.

There's not really a lot to dislike here. I've some nitpicks here and there. Honestly the weakest part of the episode for me is The Doctor and Rose. They don't actually have a lot to do in the story here (fortunately that really changes next week). They mostly just give exposition and react to stuff.

Unfortunately they're still so self-satisfied with each other in this episode. I don't really like the scene of them talking about having to settle down now they've lost the TARDIS. Firstly the Doctor already had a similar scene in 'The Girl in the Fireplace'. Secondly the awkward way they skirt around the idea of getting a house together. They hit that this is supposed to imply some sort of romance too hard, without justifying why it would. I mean they already live together and aren't romantically involved. I don't see why it would be awkward for 2 friends who already live together platonically, to discuss moving into a house without it being treated like it's this sexy, romantic notion. Well I do see why. The creative team this season were determined to push the idea of a Doctor/Rose romance, presumably in preparation of the series finale. We'll get there.