How long is the presidential debate tonight? Here's when it's expected to start and end

At long last, the final presidential debate of 2016 is upon us.

Beginning at 9 p.m., Democratic candidate Hillary Clinton and Republican candidate Donald Trump will square off on the stage of the University of Las Vegas in Nevada to discuss the issues that matter.

How long will the debate last?

The debate will come to an end at 10:30 p.m. Eastern, leaving 90 minutes for the two candidates to outline their platforms and take each other to task for their political differences.

Moderated by Fox News' Chris Wallace, the third debate will be a change in format from the second debate's town hall-style arrangement. Questions for the candidates will be posed by Wallace alone, and will focus on debt, immigration, the Supreme Court, the economy and foreign policy.

Trump and Clinton refused to shake hands at the beginning of the second debate.Robyn Beck/Getty Images

What can we expect?

Trump has already promised to keep things interesting ahead of the debate by making the unusual political decision to invite Malik Obama — President Barack Obama's half-brother — as his guest of honor for the evening.

For her part, Clinton has been diligently prepping, and will likely continue to use Trump's vulgar claims of sexual assault — surfaced in early October by the Washington Post — against him.