The first public presidential impeachment hearings in over 20 years will continue on Friday with testimony from the former top U.S. diplomat in Ukraine, who other witnesses have said was unfairly smeared and run out of her job by President Donald Trump's personal lawyer Rudy Giuliani.

When does the hearing start?

The hearing is slated to start at 9 a.m. ET Friday, an hour earlier than the first hearing on Wednesday, which featured testimony from diplomats Bill Taylor and George Kent. House Intelligence Committee Chairman Adam Schiff, D-Calif., will make an opening statement, followed by an opening statement by the ranking member on the committee, Rep. Devin Nunes, R-Calif., and then a statement from the witness.

Who's testifying?

Marie Yovanovich, who served as U.S. ambassador to Ukraine from 2016 until May of this year, when she was recalled from her post. The longtime diplomat, who President George W. Bush named ambassador to Kyrgyzstan in 2005 and ambassador to Armenia in 2008, was the subject of a disinformation campaign by corrupt Ukrainian politicians that was amplified in the U.S. by Giuliani.

Who's doing the questioning?

Schiff and Nunes will have 45 minutes each to question witnesses in the first part of the hearing. They can — and are expected to — delegate the bulk of the questioning to their committee lawyers instead. Daniel Goldman, a former federal prosecutor, is the lawyer for the Democrats and Steve Castor is the lawyer for the Republicans.

Schiff will determine if there is a need for an additional 90 minutes of questioning by the lawyers or move on to lawmaker questions. Once the staff questions conclude, the format will revert to one similar to a traditional congressional hearing, with all lawmakers on the panel getting five minutes each to ask questions.

Who's on the committee?

There are 13 Democrats and nine Republicans. The Democrats include Schiff, former presidential candidate Eric Swalwell of California and Joaquin Castro of Texas, the brother of presidential candidate Julián Castro. The other Democrats are Jim Himes of Connecticut, Terri Sewell of Alabama, Andre Carson of Indiana, Jackie Speier of California, Mike Quigley of Illinois, Denny Heck of Washington, Peter Welch of Vermont, Sean Patrick Maloney of New York, Val Demings of Florida and Raja Krishnamoorthi of Illinois.

On the Republican side are top Trump allies Nunes, John Ratcliffe of Texas and Jim Jordan of Ohio, who was added to the committee just last week. Also on the Republican side are Michael Turner and Brad Wenstrup of Ohio, Chris Stewart of Utah, Elise Stefanik of New York. and Mike Conaway and sometimes-Trump critic Will Hurd of Texas.

The hearing is set to take place in the House Ways and Means Committee hearing room because the Intelligence Committee doesn't have its own hearing room. It is the same one where Hillary Clinton testified before the Benghazi Committee for more than eight hours in 2015.

What to expect from each side

Democrats are expected to stress Yovanovitch's decades of public service, and delve into the disinformation campaign against her that led the president to declare she was "bad news." Republicans are expected to focus on the fact that the president can remove an ambassador for any reason whatsoever.

How long will the hearing take?

To be determined, but it is expected to be shorter than Wednesday's hearing, which lasted about 5 and a half hours.

Where can you watch?

NBC News will air a special report beginning at 9 a.m. ET led by "NBC Nightly News" anchor Lester Holt and NBC News chief legal correspondent Savannah Guthrie. NBC News political director Chuck Todd will join from Washington, DC, and NBC News chief foreign affairs correspondent Andrea Mitchell and NBC News chief foreign correspondent Richard Engel will join from New York.

MSNBC will have special coverage beginning at 9 a.m. ET anchored by "Deadline: White House" host Nicolle Wallace and "Hardball" host Chris Matthews.

The hearings will be streamed live on NBC News NOW, NBCNews.com and MSNBC.com. NBCnews.com will also feature a live blog with contributors from across NBC News with news, fact checks and analysis. The coverage will be collected at NBCNews.com/impeachment.

Are more public hearings scheduled?

The Intelligence Committee announced it will hear testimony from 8 witnesses over three days next week.