The Genius of Britain Season 1 Episode 1 (The Genius of Britain s01e01) with title “Defying Gravity: The beginnings of British science” airs on Sunday, May 30th 2010 at 09:00 pm via Channel 4.
Here is summary for The Genius of Britain :

Genius of Britain sees Richard Dawkins, James Dyson, Stephen Hawking, David Attenborough and Robert Winston celebrating the great thinkers and moments from the history of British science from Issac Newton right up to the modern day.

Few hours after original series aired on TV, online streaming video for The Genius of Britain Season 1 Episode 1 usually available on Net and of course, if video available, as soon as possible will show you where you can watch this episode for free.