Here's the Doctor Who-related moment that caused all the fuss a while back. In today's Sarah Jane Adventures, Clyde asks the Doctor how many times he can regenerate. The answer may surprise you. Spoilers ahead...

So yes, it's probably a joke, given the way Matt Smith delivers the line. Everybody who said so all along can gloat a bit. At the very least, if Doctor Who decides to re-impose the limit of twelve regenerations at some point down the line, they don't have to worry about contradicting this tossed-off moment of bonding between the Doctor and the best companion he never had. (Am I the only one who is crying out for a whole season of the Doctor traveling with Clyde and Rani?)

So part two of "The Death Of The Doctor" was just as much of a joy as part one was yesterday, although it did have a bit of the typical Russell T. Davies "slightly magical solve all your problems by thinking of the Doctor" ending. Still, this story wasn't really about whether the Shansheeth were going to be able to make their own TARDIS key and go around the space/time continuum conquering death. It was about grappling with the meaning of death itself — and to a much larger extent, it was about Davies' favorite theme, the way in which the Doctor changes people.

Davies comes dangerously close to doing a re-run of his first Sarah Jane story, "School Reunion," with Jo — but to his credit, he remembers that Jo's leaving was very different than Sarah Jane's, and Jo was a very different companion. Not only was Jo as dotty as all get-out, she also ran off to travel the Amazon with her own mad professor. And she's just as useful a companion to the Doctor as Sarah Jane — Jo brings the odd inspiration, like her blackcurrant oil, while Sarah Jane brings a more practical help, her sonic lipstick. As the Doctor says, they make a good team. (And I love the line about transdimensional displacement with just a hint of blackcurrent. Classic.)

When Davies does do the "companion processing her feelings about the Doctor" scene, it's remarkably affecting, especially when the Doctor says he was proud:

Something about the idea of the Doctor taking pride in his old companions is really sweet. Although now I want to see an ex-companion turn evil and horrify the Doctor, possibly becoming a major villain. (Not just Adam from season one, who's a villain waiting to happen, but somebody major — like, say, Ace. Or even Martha.) I have to admit, this episode pandered to me as an old-school Who fan almost too well, and I'm sort of in love with the idea that Ian and Barbara haven't aged since the sixties. (Side effect of the Dalek time machine?)

So we sort of pick up episode one's focus on how grieving is all about memory, and memories have power — because, as Davies point out, they can open doors. And this is picked up in Sarah Jane's slightly cliched but still awesome final line, about how as long as there are all these "echoes of the Doctor" around, he'll never really die. The Doctor has shown all his former companions a better way to live, and that in turn helps them to remember him.

It's funny that a story which was rumored to be making the Doctor immortal turns out to convey the message that the best immortality the Doctor can ever have is to be remembered by his friends.

So what did you think?