I posted this in response to a Reddit thread last night, but I thought you guys might enjoy it.
In November of '63, JFK got shot.
Doctor Who would premiere, but instead it did not.
The world had to wait just one week longer,
to see the Doctor appear, so viewership would be stronger.
The Doctor was a man, who wasn't a man.
He looked very old, and always had a plan.
He traveled space-time with his granddaughter,
Fighting Daleks, and Sontarans, and Jibbldygogglers.
In the first episode two teachers spied,
the Doctor's blue box, "bigger on the inside!"
The Doctor and his kin traveled for a time,
until the actor got sick, no longer feeling his prime.
But the show did well, and it's fans venerate,
so the creators said, "why, he'll regenerate!"
So Hartnell stepped down, giving Troughton his due,
playing the same man, although, different, too.
"The Doctor's a Time Lord! An alien!" they said,
"He doesn't die, he just changes instead!"
And so the Doctor's legacy would continue on,
first as Troughton, then Pertwee, Baker, and Davison.
He was a Time Lord, that much you knew,
but there were other Time Lords, just like him, too.
They weren't very nice, even the nicer ones,
always chasing him down, so he'd be on the run.
The Master was the worst, the Doctor's arch-rival,
and no matter what happened, you could count on his survival.
The Doctor travelled in a box, always doing what's best,
no longer with his granddaughter, she had to leave the nest,
but with new companions, like Sarah Jane, Ace, or K9
they were all sorts of people, each given a chance to shine.
Romana, the Brigadeer, the list goes on and on,
as it should, since the show's run for 50 years (it's not gone)!
But something sinister would happen in '89,
poor reception and low ratings meant that it was time.
The show would be cancelled, the fans would be ignored.
A dark time for our fandom, now they would be bored.
They tried a revival in the 90's, for fans to look at,
but it was really bad, let's not talk about that.
And so for awhile, it seemed memory of the show was getting hazy,
when out of the ashes rose a man, "Russel T. Davies!"
Davies was a fan as a kid, who wanted the show back,
so he told the BBC there was something they lacked.
He cast Eccleston, as a 9th Doctor,
and he cast a pop singer as Rose (this show would be hotter).
But terrible things happened to our old Time Lord friend,
an enormous war had brought his species to an end.
Fighting the Daleks, the two species warred,
until the Doctor became the last of the Time Lords.
So he travelled with Rose, running from his past,
and the fans who were watching were having a blast!
But Eccleston no longer wanted to be the role's tenant,
So along came a fan favorite, David Tennant!
The new show was edgier, but had it's charm too
(and the special effects no longer blew).
It had it's low points, like alien farts,
but it also had what it needed, a whole lot of heart.
Piper left the show, and we got Martha Jones,
the Doctor after all, shouldn't be alone.
The stories were good, kept you on the brink,
during the scary ones, "don't blink!"
And along came our good friend the Master,
the Daleks were back too, oh what a disaster.
Donna came along, but then she forgot it,
and the Doctor felt bad, because he had wrought it.
Then Tennant left too, giving us Matt Smith,
Davies left showrunner, leaving us with,
a guy who would surely make the show profit,
fan-favorite writer Steven Moffat.
The new show was darker, but a fairy tale too.
Kept you hiding your eyes, and wondering "Doctor Who?"
And that's where we are, with Amy, Clara, and River,
and it Hurts me to wait to see the show deliver,
it's 50th-year special this November,
we'll see David, and Matt, finally together.
And the show will continue, past 10 and 11,
and in my opinion watching the show is heaven,
because Doctor Who is about such magnificent things,
like a fairy tale filled with science and kings.
As far as shows go, Doctor Who is pretty fun,
so for now I've got just one word. Run.