A televised leaders’ election debate is a bit like the Rapture. The prospect of it comes around every few years, it’s discussed with a mixture of dread and scorn, no one can decide on the exact date, and everyone assumes it probably won’t happen.

But the End of Days has at last arrived. And here’s what you need to know to prepare yourself for an Armageddon of soundbites, late nights, and shiny foreheads.

Thursday 16 April, BBC

Debate between the five opposition party leaders

This has been dubbed the “challengers’ debate” – though when it was first referred to in a Spectator piece revealing the Tories' offer, I rang round the potential participants and none of the smaller parties seemed to have heard of it – and nor had the BBC.

With Labour's rather risky decision for Miliband to take part, it’s now being referred to as a debate between the five opposition leaders (everyone but Cameron and Clegg): Farage, Bennett, Sturgeon, Wood, and Miliband. The BBC is labelling it the Election Debate.

The debate will be moderated by David Dimbleby. It take place at Central Hall, Westminster, and broadcast live on BBC One, the BBC News Channel, BBC Radio 5 live and online from 8pm until 9.30pm.

From left to right, the leaders will be standing in this order: Ed Miliband, Leanne Wood, Natalie Bennett, Nicola Sturgeon, and Nigel Farage. They drew lots on the order this week.

Each will make a short opening statement, and then Dimbleby will introduce questions from a studio audience of 200 voters, who have been selected and weighted to give a cross-section of political opinion.

Here's the order in which they'll make their statements: Leanne Wood, Nigel Farage, Ed Miliband, Nicola Sturgeon and Natalie Bennett.

The debate will feature five questions, with each leader given a minute to offer their own answer before 10 minutes of free debate. At the end of the debate the leaders will be invited to make short closing statements.

Full running order:

Opening Statements

1. Leanne Wood

2. Nigel Farage

3. Ed Miliband

4. Nicola Sturgeon

5. Natalie Bennett



Question One

1. Nicola Sturgeon

2. Ed Miliband

3. Natalie Bennett

4. Nigel Farage

5. Leanne Wood

Question Two

1. Ed Miliband

2. Leanne Wood

3. Nigel Farage

4. Natalie Bennett

5. Nicola Sturgeon

Question Three

1. Nigel Farage

2. Natalie Bennett

3. Leanne Wood

4. Nicola Sturgeon

5. Ed Miliband

Question Four

1. Natalie Bennett

2. Nicola Sturgeon

3. Ed Miliband

4. Nigel Farage

5. Leanne Wood

Question Five

1. Ed Miliband

2. Nigel Farage

3. Nicola Sturgeon

4. Leanne Wood

5. Natalie Bennett

Closing Statements

1. Nicola Sturgeon

2. Leanne Wood

3. Natalie Bennett

4. Ed Miliband

5. Nigel Farage

Thursday 2 April, 8pm, ITV

Seven-way panel

This will be a straightforward panel debate involving seven party leaders: Natalie Bennett, Nigel Farage, Nick Clegg, David Cameron, Ed Miliband, Nicola Sturgeon and Leanne Wood.

It will be moderated by Julie Etchingham, the ITV News at Ten presenter. While acknowledging the complexity of dealing with such a big number of debaters, and warning that she will be “sharp” in making sure they stick to their timings, Etchingham told the Guardian: “Given we have a new political landscape emerging, it’ll be fascinating to see how they all interact.”

The format will allow each leader to give an uninterrupted answer to a question and then the debate will be opened up into a moderated discussion between the leaders, for up to around 17 to 18 minutes on each question.

The studio audience selected will be demographically representative of the country as a whole and politically balanced.

ITV will ask the selected audience for their questions, as well as ITV viewers, who have been asked to submit questions via debate@itv.com

Studio audience questions and viewer questions will be seen by an experienced editorial selection panel, who will decide which questions go forward to the debate on the night. If viewers' questions are chosen, these viewers will be invited to be a part of the audience.

It begins at 8pm, and will be a live, two-hour show. Here is a graphic of when everyone will speak (via May2015.com).

Thursday 30 April, BBC

Question Time special

One week before polling day, the BBC will host a special Question Time programme with Cameron, Miliband and Clegg taking questions from a studio audience. Each leader will appear separately on the programme. Dimbleby will again present.

More to follow.