Play by play:
We meet a jewel thief, complete with Mission Impossible style personal lowering-from-high-places improbably fast winch stealing what looks like the Holy Grail. (It's not. Well, it's a grail, but not very holy.) The guards are slightly more alert than she anticipates, and after the alarm is sounded she has to make a run for it. She hops a bus to escape the police, and a Converse wearing, psychic paper bearing stranger gets on the bus, sits next to her, and offers her some candy. It's the Doctor (of course) and he's in full on 'detecting anomaly' mode. As the bus goes into a tunnel, the wormhole that he's trying to detect swallows the bus and lands them on Tatooine.
The bus driver attempts to walk back through the wormhole, but bursts into flames on his way back through and becomes rather skeletal. The police (wisely) call U.N.I.T... who show up immediately with enough military hardware to make Margaret Thatcher beam with pride. Meantime, on the other side, the Doctor does his (patent pending) cell-phone trick and calls UNIT. After a metric tonne of hero worship, we meet a scientist who apparently is a genius, and the officer in charge of this little UNIT taskforce. The wormhole is growing... but why and what for?
The Doctor and Lady Christina (our jewel thief who bears a startling resemblance to Jaime Sommers from the recent Bionic Woman reboot, but this time with a British accent (YES. I KNOW it's the same actress. It's HUMOR, boy! Watch it fizz....le))set off across the sand and are found by a rather large housefly. The housefly has a spaceship that also crashed unexpectedly. The Bionic Thief makes some astute observations. The Doctor makes some more astute observations. The Bionic Thief starts to remind me of a weird combination of Romana, Ace, and Leela. (At this point, I was SURE she was gonna die horribly... because I LIKED her). The Doctor figures out a way to get the bus back to Earth, she implements her own plan to do it, the Doctor saves her life... she uses her umpteenth level thief skills to get the magic wheel clamps, and theres a bit of running.
And houseflies die horribly.
The Doctor flies Chitty Chitty Double Decker Bus through the wormhole, Malcom the scientist closes the wormhole and UNIT gets to use all that lovely ordinance that they brought to the party.
And the Bionic Thief Companion-like person lives- as does everybody that the Doctor promised to get home alive-- the first time I can remember that he actually keeps that promise (He never promised anybody in The Empty Child two parter anything). And so, when he heads toward the TARDIS (That UNIT so helpfully transported to him), we expect the smart, lovely and super resourceful Lady Christina to accompany him....
He a) turns her down cold, b) allows her to be arrested by the police.
He helps her escape, and she steals Chitty Chitty Bang Bus and flies off. Obligatory Psychic Lady tells the Doctor that his song is about to end and that he will "Knock Four Times". The Doctor looks concerned and puzzled because the Tony Orlando and Dawn song was "Knock Three Times" ... so now we know that the Tennant Doctor dies in a horrible Karaoke accident.
The science in this episode was up to Doctor Who standards- which is to say... really, really horrible. We have steel-clad stingrays that create a wormhole by orbiting a planet really fast.
The Bionic Thief was an excellent companion. As she's still alive, she may still become one. Probably not, though Torchwood is hiring...
Only three dead bodies, if you don't count the sand. And only one human, and nobody that the Doctor promised safe passage home died.
Yet another 'Doctor and a bunch of ninnies on a bus/shuttle/doomed ship" plot. Except these are less ninnies than some of the previous outings... it feels the same as a few other recent episodes. I'm very glad that Russell T. Davies tenure as keeper of the flame is about to expire. I am grateful for what he's done to revive the Doctor, but I'm really looking forward to what Stephen Moffat is able to do as show-runner.
Lee Evans does a great job as Dr. Malcom Taylor- he'd also make a fun companion.
Overall, a nice diversion. I enjoyed it.