UPDATE 10/19 8:15 p.m. ET: Follow the final debate with Us Weekly's live blog for by-the-minute updates and a livestream of the event! The post also includes all of the latest social media reactions to the most noteworthy moments! 

UPDATE 10/19 6:45 p.m. ET: Condoleezza Rice had the perfect response to Donald Trump calling her a "bitch." When CNN reached the former secretary of state for a comment ahead of Wednesday's final presidential debate, Rice simply responded, "Can't wait until November 9!"

UPDATE 10/19 5:10 p.m. ET: Chris Wallace, moderator for the third and final 2016 presidential debate and son of the late Mike Wallace, reveals an exclusive list to Us Weekly of 25 surprising facts about himself, including the time he beat Michael Jordan at basketball and his reaction to getting arrested. 

Original story below:

The train wreck that is the 2016 presidential election is about to make its third and final stop on a debate stage, as Donald Trump and Hillary Clinton face off in Las Vegas on Wednesday, October 19. With just three weeks remaining before America picks its commander in chief, the candidates will tackle questions ranging from foreign policy to fitness for office.

The first two debates have been contentious, to say the least, but this third event is likely to get extra heated in light of the October surprises that have plagued both candidates' campaigns. Clinton may have to answer for the information contained in purported WikiLeaks transcripts of her previous speeches to big banks — and Trump is almost certainly going to be hit with tough questions about his alleged contact with multiple female accusers. In other words, it's going to be a must-watch! Here's what you need to know before you tune in.

The Basics

Welcome to Vegas, baby! The third and final debate will take place Wednesday, October 19, at the University of Nevada, Las Vegas, from 9 p.m. to 10:30 p.m. ET. Like its predecessors, this event will run commercial-free; you can watch it via livestream from Us Weekly's live blog of the debate, and it also airs on all major TV networks.

The Moderator

Chris Wallace, the Emmy-winning anchor of Fox News Sunday, will be holding down the moderator's table singlehandedly — and both candidates should be prepared for hard-hitting questions and zero tolerance for shenanigans. Wallace is known for being a forceful interviewer, which makes him exactly the right guy to keep this debate from veering off the rails.

The Questions

Sorry, wannabe Ken Bones: There won't be any undecided voters on stage with Clinton and Trump this time around. Wallace will be fully in charge of selecting questions for the candidates, which will cover six distinct areas of discussion: entitlements and debt, immigration, the Supreme Court, the economy, foreign policy and — the likely hot topic of the evening — the fitness of each candidate for the highest office in the land.

The Pre-Debate Prep

One thing you can say for our candidates: They're definitely consistent! Clinton, whose intense preparation for the first two debates paid off in the form of composed and decisive (albeit slightly rehearsed-feeling) performances, has once again cleared her calendar and disappeared from public view to be as ready as possible for Wednesday's event.

Trump, who not only didn't prep for the first two debates but criticized Clinton for suspending her campaign activities in advance of the last one, seems to be planning to wing it this time too. He has had events scheduled right up through the afternoon of Tuesday, October 18 — and when he's not in front of a microphone, he's using his Twitter account to complain that the election, media coverage and even the upcoming debate itself are all "rigged."

Some celebrities are getting in on the pre-event prep, most notably Madonna and Eminem. On Tuesday night, the Queen of Pop opened for Amy Schumer at Madison Square Garden and shared her support for Clinton by making a very NSFW proposition to the audience. "If you vote for Hillary Clinton, I will give you a b--wjob — and I'm good!" she declared.

As for the rapper, 44, he dropped a diss track about the Republican presidential candidate and conservative supporters early on Wednesday. The new tune, titled "Campaign Speech," includes the lyrics: "Consider me a dangerous man / But you should be afraid of this dang candidate ... And that's what you wanted?/ A f--kin' loose cannon who's blunt with his hand on the button / Who doesn't have to answer to no one?/ Great idea!"

The In-Debate Tactics

Clinton and Trump have debated each other twice now, which means that we know roughly what to expect from both candidates when they take the stage for their final face-off. Trump will bring up the ongoing issue of Clinton's private email server, possibly threaten to have her thrown in jail if he becomes president, and almost definitely manage to create the evening's most memeworthy moment (much like his widely lampooned lurking from the second debate). And Clinton, for her part, almost certainly won't miss the opportunity to hit Trump where he's weakest: the woman issue. (Half a dozen accusations of sexual misconduct have been leveled against the GOP nominee since the leak of his now-infamous 2005 conversation with Billy Bush.) 

Trump, meanwhile, is again bringing last-minute guests. The mogul invited President Barack Obama's half brother Malik Obama to the debate. (He previously brought a group of women who accused Bill Clinton of sexual assault to the second presidential debate.) In July, Malik revealed that he supported Trump. 

"I look very much forward to meeting and being with Malik," Trump told the New York Post. "He gets it far better than his brother." Malik added: "I’m excited to be at the debate. Trump can make America great again."

But with no more debates planned and only three weeks before Election Day on November 8, both candidates have good reason to hit their hardest this Wednesday night — and we have good reason to think it will be their most heated confrontation yet.

Be sure to join Us as the event unfolds for a minute-by-minute live blog. The third and final 2016 presidential debate airs on all major networks Wednesday, October 19, at 9 p.m. ET.  

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