Doctor Who joke :D

I came up with a joke today :)

It goes like this:
What is a very popluar science fiction programme about ghosts?
Doctor Boo! :D

All my friends though it was rubbish, but I thought it was hysterical lololol
Then again, I was hyper on sugar nom XP

Kinda makes me think of this:
A new incarnation of the Doctor perhaps?

...anyone?