Is there life on Mars?

Last night durham_rambler and I watched the very last episode of Life on Mars. I was so pleased that it was being repeated, and that I would have the chance to enjoy something that people were enthusing about. And I enjoyed the first couple of episodes very much: they were sharply scripted, witty, intriguing entertainment. But by the time the BBC upped the dosage from one to two installments a week, although durham_rambler stuck with it, I discovered I didn't care enough to give it that much of my time. I saw one or two more episodes, when I was in the mood, didn't feel I was having any trouble following the story, and came back on board for the dénouement.

( I suspect that everyone who cares about this is way ahead of me here, but just in case. Also includes random spoilers for a couple of books. )

And now it's time for Heroes.