With Clinton, along with some Republicans, attacking Trump over his comments on women, and Trump already discounting the election results as "rigged," all eyes will be on the last matchup between the candidates before Election Day.
The debate, moderated by Fox News' Chris Wallace, will focus on topics including the economy, debt and entitlements, immigration, the Supreme Court, foreign "hot spots" and fitness to be president, according to the bipartisan Commission on Presidential Debates.
The political fireworks will kick off at 9 p.m. ET on Oct. 19 at the University of Nevada, Las Vegas. You can watch the debate live below.