The debate, this time on foreign affairs, will be shown live on Sky News from 8pm. We'll begin the chat at 7:30pm and from the team we'll have Jon Bernstein, James Macintyre, Sophie Elmhirst and myself offering live views and reaction.
So, will Nick Clegg come out fighting after the right-wing attacks on him? Will David Cameron get the victory he needs? And will anyone say "I agree with Nick"? Join us from 7:30 to find out.