Highlights from this year's Comic Relief - Face the Funny.
A celebrity-packed behind-the-scenes look at how the legendary night of TV comes together.
Brett Domino rises to the challenge of writing a hit charity song in record time.
David Walliams' Little Britain character Lou meets Professor Stephen Hawking.
Comic Relief has always undertaken big challenges, but none quite match the scale and endeavour of this year's - in a matter of weeks, a team led by Lenny Henry gives a full makeover to a rural health centre in Uganda.
The staff say that their health centre might be the worst in Africa, and when the Comic Relief team turned up they found semi-derelict buildings, with no electricity and no running water, that were infested with rats and other vermin. Many patients were simply too scared to stay the night there.
Lenny brings a stellar cast - including Richard Hammond, Dermot O'Leary, John Bishop, Steve Backshall, Greg James and Doon Mackichan - to help transform Iyolwa into a fully functioning health centre serving its community. But the real heroes are locals like Francis the doctor, Dorothy the midwife and Gonza the master builder, faced with the gargantuan task of making it all ready for Red Nose Day.
Sir Lenny Henry takes a look back at a night of comedy and fundraising in this special programme featuring the very best of Red Nose Day 2015.
Sir Lenny pays a return visit to Iyolwa health clinic in Uganda to see how the money raised is dramatically changing people's lives, while John Bishop returns to Kenya and Alex Jones reports back on Comic Relief projects in the UK.
Plus, there are comedy highlights including Little Britain, The Vicar of Dibley and Mr Bean.