Dinosaurs on a Spaceship is 98% cheese with a serving of ham (and very good ham it is, too) and 2% unexpected darkness.
It gives us dinosaurs on a spaceship, Rory's father, Queen Nefertiti, a big game hunter whose name I may or may not be supposed to recognize, slapstick robots, a triceratops playing fetch... with a particularly nasty genocide in the background, the threat of rape, and the Doctor committing deliberate, cold-blooded murder.
A lot of it is pure fun. The Doctor, who has been saving Ancient Egypt while we weren't watching, is just saying a fond (on her part, at least) farewell to Queen Nefertiti when he gets an emergency call from Earth and runs off. Queen Nefertiti, following the time-honored tradition for Companions, follows him in uninvited. Once the Doctor learns of the situation--a spaceship is on a crash course for Earth, and if it isn't stopped, it will be shot down, the Doctor decides he needs more help and goes on a collecting expedition, picking up Amy, Rory, and (accidentally) Rory's dad by materializing around them and then nabbing a big game hunter to round out the "gang."
The "gang" splits up and runs around the spaceship, pressing buttons, running away from dinosaurs (the Doctor is almost as glad to see dinosaurs on a spaceship as he was to see a werewolf with Rose), flirting, and finding out what's up.
All of which is delightful fun. Every member of "the gang"-even, eventually, Rory's dad, are having the time of their lives. Amy has fun figuring out an alien computer and trading quips with Nefertiti. Nefertiti and the big game hunter flirt, and, in the end, Rory's dad has a picnic, sitting in the TARDIS doorway, watching earth (And I nominate that as one of the single most adorable, wonderful moments in the program. It's a moment of pure, innocent wonder, and I loved it.). The whole situation is completely over-the-top; in short, it's vintage Doctor Who, a lovely, unlikely mishmash of genres and characters that somehow holds together as it careens toward a conclusion.
But. There's that 2%. It also turns out that the villain who hijacked the ship is a nasty piece of goods who deliberately woke up the hibernating crew (Silurians) a few at a time so that he could space them while they were conscious. He claims Nefertiti as his prize, promising to break her (That's quite some database he's got, incidentally. Nefertiti is how long ago in his time? And it's not like we have perfect photos of her as she lived).
Then the Doctor comes up with a plan that saves everyone except for the villain. The villain, he deliberately sends to his death, not because he needs to die to save their lives, but just because he's disgusted. This, by the way, is the Doctor who wouldn't kill the Daleks when he had the chance, who refused more than once to kill Davros, who gave the invading Sontaron's a half dozen or more "last chances," and who went to infinite pains to reshape Kazran's past in A Christmas Carol. In short,the Doctor does not kill. He is not even in one of his rages when he does it; it's more a motion of weary disgust. What is more, the episode glosses over the Doctor's decision without beat or pause in its frenetic pace. It simply does not fit with the rest.
So: Is that 2% some sort of foreshadowing of things to come, an indication of past events, or simply a misstep on the part of Chibnall and Moffat?
I don't know what I think, and I'm not sure I like that. Oh, I still like Doctor Who, but Moffat's reign has involved a series of mostly-satisfying episodes with some very long term question marks, some running for more than a season, and I'm starting to think that my enjoyment of arcs isn't quite as strong as I thought it was.
Edit: Since I wrote this, I have remembered and have been reminded of a number of times when the Doctor did directly act to kill--including last episode when he used one Dalek to destroy a number of others. However, what troubles me about this is that the episodes I've seen him kill (I am not conversant with all the Old Who episodes people have cited, but can think of The Runaway Bride and Family of Blood, for example), he's been in a rage, and even so, has generally offered several options before killing. This was a cold, calculated killing. The Doctor took the time to explain to Solomon exactly what was going to happen, and he did so calmly. This is a change from any of the Doctors, and it is definitely a change from the more playful Eleventh Doctor we saw in The Eleventh Hour. It seems as though something happened between this season and last season to create the weary disgust present in both episodes (His response to the woman's request at the beginning of Asylum of the Daleks is to wish people wouldn't talk about his wonderful ability to save others).
Incidentally: Yes, I did notice Solomon's database not spitting out his name. Was everyone hacking into the Daleks' computer for information?