Summary: The top ten is revealed and a debate on the merits of each ensues in the studio.

Summary: Jeremy Clarkson argues the case for Isambard Kingdom Brunel.

Summary: Did The Origin of Species make Charles Darwin the greatest ever Briton? Andrew Marr makes his case in the Galapagos Islands - where Darwin first witnessed evolution at work.

Summary: Writer and broadcaster Rosie Boycott makes the case for choosing Diana, Princess of Wales, as the greatest Briton of all time.

Summary: Historian Richard Holmes assesses the achievements of Oliver Cromwell, the military leader whose passionate belief in the rights of the common man saw him sow the seeds of modern-day parliamentary democracy.

Summary: Historian and writer Lucy Moore makes the case for choosing Horatio Nelson as the greatest Briton of all time.

Summary: Actress Fiona Shaw explores the author's identity and applauds him for writing about life in a way that all could understand.

Summary: Consigned to the Tower of London in her youth, Elizabeth I survived to turn Britain into a world power. Michael Portillo argues the case for the queen as being the most remarkable leader this country has ever had.

Summary: Isaac Newton is best remembered for the story of the falling apple - the inspiration for his theory of gravity. Historian Tristram Hunt argues, however, that there was much more to Newton than this.

Summary: First with the Beatles, then as a solo star, John Lennon revolutionised 20th-century music. Jonathan Creek's Alan Davies celebrates an icon for the post-war generation who communicated in a universal language - pop music.

Summary: In the summer of 1940, Britain looked to Prime Minister Winston Churchill to stem the imminent invasion by Hitler's forces. Since he fulfilled his destiny and led Britain to victory, Mowlam proposes Churchill as the greatest Briton.

Summary: Anne Robinson is joined by the celebrities who championed the ten nominees while the final votes are cast.