The House Intelligence Committee kicked off public impeachment hearings on Wednesday as part of the inquiry into President Donald Trump. Bill Taylor, the top U.S. diplomat for Ukraine, and George Kent, the deputy assistant secretary of state for European and Eurasian affairs, appeared before lawmakers to answer questions for five hours. Here are six moments you don’t want to miss:

1. Taylor says a staffer heard Trump ask about ‘the investigations’

Taylor told lawmakers that one of his staff members overheard a phone call in which the president asked Gordon Sondland, the U.S. ambassador to the European Union, about “the investigations” that he wanted Ukraine to open. After that conversation between Trump and Sondland, which occurred one day after Trump spoke with the Ukrainian president, the staffer was told by Sondland that Trump cared more about the investigations into the Bidens than about Ukraine.

2. GOP counsel asks if Trump’s efforts could have been more ‘outlandish’

Republican counsel Steve Castor asked whether it was out of the norm in the U.S. government for there to be two lines of diplomacy, as Taylor had stated — one official and one unofficial. “In fairness, this irregular channel of diplomacy, it’s not as outlandish as it could be. Is that correct?” Castor said.

“It’s not as outlandish as it could be. I agree, Mr. Castor,” Taylor said with a laugh. Castor went on to question whether it was unusual for Sondland, who represents the U.S. to the EU, which does not include Ukraine, to be involved with Ukraine affairs. “It is a little unusual for the ambassador to the EU to play a role in Ukraine policy,” Taylor responded.

3. Taylor says withholding Ukraine aid isn’t just ‘crazy,’ it’s ‘wrong’

Taylor had expressed concerns about the Trump administration’s actions on Ukraine, at one point describing the policy as “crazy” in a text message. He even threatened to quit over Trump’s demands. On Wednesday his words were even stronger.

“Holding up of security systems that would go to a country that is fighting aggression from Russia for no good policy reason, no good substantive reason, no good national security reason, is wrong,” Taylor said in an exchange with Rep. Eric Swalwell, D-Calif.

4. A tense exchange between Reps. Jim Jordan and Peter Welch

Rep. Jim Jordan, R-Ohio, repeatedly called to hear testimony from the whistleblower, who Jordan described as “the reason we’re all sitting here today.” Rep. Peter Welch, D-Vt., dismissed Jordan’s request, but instead invited Trump to testify as “the person who started it all.” The moment prompted laughter in the room.

Republicans have continued to call for the whistleblower to come forward with their complaints, despite legal requirements to protect their identity.

5. Kent and Taylor believe Giuliani’s interests in Ukraine were to ‘dig up political dirt’

Responding to questions from Rep. Val Demings, D-Fla., Kent and Taylor explicitly stated their beliefs that Trump’s personal lawyer, Rudy Giuliani, was looking to dig up information on a political rival to assist Trump in the next election cycle. Giuliani’s role has been a focal point in the inquiry, as the lawyer, who does not work in foreign policy, held a number of meetings with Ukrainian officials on Trump’s behalf.

6. Kent says there’s no basis for Trump’s allegations against former Vice President Joe Biden

One of the big talking points for Trump and Republican lawmakers has been the accusation that former Vice President Joe Biden helped push out a Ukrainian prosecutor in order to protect his son from a corruption probe. When asked whether there is factual basis to support the allegations against the Bidens, Kent responded, “none whatsoever.”