Nigel Farage and Nick Clegg will go head-to-head on Wednesday evening in the first of two debates on the future of Britain's membership of the European Union.
Tonight's debate will be hosted by LBC radio presenter Nick Ferrari in front of a studio audience in central London. It will last for one hour, starting at 7pm. The order in which the two men speak will be decided, appropriately, by the flip of a euro coin.
The audience has been selected to reflect the UK population as well as a spread of views on the EU debate. Questions will be screened by an editorial panel but the parties will not see them in advance.
The party leaders will both make opening and closing statements and will have one minute to answer questions from the audience before Ferrari opens up the subjects to free debate.
Commenting ahead of the debate, Ferrari said: "This is the debate the nation has been waiting 40 years to hear. The questions are as tough as they come.
"For instance, why did Nick Clegg want a referendum in 2008 but has now backed away? Why does Nigel Farage feel like he's in a foreign country until he gets to Kent on the train? These are just a couple of examples of what the two leaders will face – and they're the easy ones."
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The Ukip leader has bet everything on his party doing well in May's European parliamentary elections. Anything other than first place will be seen as a disappointment. And third place would be a disastrous result that Farage has admitted would probably see him ousted as leader of the party.
The deputy prime minister will be hoping a good showing in the debates will prevent the Lib Dems being wiped out in May. Clegg's party has taken a battering in the polls and he will not want to lose too many of his 12 MEPs with just one year to go until the 2015 general election.
Although the debate is a direct argument between Farage and Clegg, it is arguably possible for both to 'win' the debate. The two men are not chasing the same votes.
Farage sees the debate as a chance to convince eurosceptics voters that Ukip are the authentic anti-EU voice and that a vote for David Cameron is wasted. For Clegg, the debate (it was his idea) is part of a deliberate strategy to lock up the not insignificant pro-EU vote.
Anti-EU Conservative MPs, while sharing many of Farage's views on Brussels, would rather he did not steal eurosceptic votes from them. And the more europhile Tories are unlikely to want to see the argument for leaving the EU gain ground.
Defence minister Anna Soubry is one of them. "Of course I want Clegg's views on Europe to win," she told the BBC today. "The people of Britain will vote in favour of staying within the EU because most people in this country are sensible, moderate, people who will see the benefits of a reformed union."
The debate will be broadcast on LBC as well as on Sky News. Follow the LBC Twitter worm live on LBC.co.uk.
The second debate will be held next Wednesday, April 2, on the BBC. It will be hosted by veteran Question Time chair David Dimbleby.