Did you watch The Science Of Doctor Who tonight then? I thought it was excellent - Brian Cox in The Royal Institution, teaching people how space and time works and how it's possible to time travel etc., nicely linked into Doctor Who. Not dumbed down, but a great way of making it accessible to all sorts of people that wouldn't normally watch something like that. And being at the Royal Institution, it had their usual quality visual demonstrations of course! Fantastic stuff
IMO the last talk he did at the RI was much better 
the last half especially. I have a link to it on YT somewhere.