We’ve had months of set-piece events, tightly controlled by a team of campaign staff. Well, that’s about to end.
On the debate stage, candidates are on their own and in the whole campaign, this is the moment most fraught with risk.
Plenty can go wrong, so hold on tight.
Here’s your handy guide.
When – and where – are the Trump v Biden debates?
There are three presidential debates on the agenda:
29 September in Cleveland, Ohio
15 October in Miami, Florida
22 October in Nashville, Tennessee
Vice-President Mike Pence and Senator Kamala Harris will also go head-to-head:
7 October in Salt Lake City, Utah
They all take place from 21:00-22:30ET (02:00-03:30BST), with no commercial interruptions.
What’s the format for the first debate?
Six questions in six segments, 15 minutes each. The segments are:
Mr Trump and Mr Biden will get two minutes apiece to respond to the question initially before the back-and-forth begins.
The first moderator is Fox News Sunday anchor Chris Wallace .
A lot of people might think a Fox News anchor would give President Trump an easy ride but this is no Sean Hannity. Quite the opposite. The president has endured some of his most awkward moments sitting across from Wallace, whose command of the detail is legendary.
An interview in July went viral when Wallace told Mr Trump he’d taken the same cognitive ability test the president touted, telling him it was “not the hardest test”.
Mr Trump – who typically favours Fox News – has dismissed Wallace as a “wannabe” of his father, Mike Wallace, who was an original reporter with CBS 60 Minutes.
A registered Democrat, Wallace has said moderating debates is a serious business as it helps “millions of people decide who we’re going to elect”.
For the second debate, we’ll have C-Span’s political editor Steve Scully moderating. That’s a town hall format which means real people get to play a part too.
Finally, NBC’s White House correspondent Kristen Welker will round out the debate season.
USA Today Washington Bureau Chief Susan Page will tackle the one and only vice-presidential debate.