There are very many ordinary people in the country who are concerned at levels of immigration, concerned at the social effects of Islam and concerned at the threat that multiculturalism poses to their traditional way of life. The main parties have largely ignored these concerns, and as a result a million voters have cast their ballot for the BNP.
The BBC is setting up Question Time to offer Nick Griffin a mass public show of distaste; from both the panel and the audience, he faces belittlement, bullying, undermining and hostility. This is probably calculated to demonstrate the distaste for the BNP's racism that most people have, and calculated to show the TV audience how mistaken they would be to vote for the BNP.
However, the BBC needs to be very careful this doesn't backfire; ordinary people who have had their own concerns - any everyone imagines their own concerns are reasonable - pooh-poohed by the political class will watch not a fascist bully-boy getting his come-uppance but themselves getting a kicking.
It will make for must-watch TV, anyhow.