Originally Published: 06 OCT 21 11:14 ET

By Jeremy Herb, CNN

(CNN) -- In the days before Rep. Adam Schiff became then-President Donald Trump's chief congressional nemesis, Trump praised the man who would go on to epitomize his toxic relationship with Democrats on Capitol Hill.

"You know, you do a good job," Trump told Schiff in the Oval Office in March 2017, according to new details from an upcoming book written by the House Intelligence chairman and obtained by CNN ahead of its release next week.

Schiff, who went on to lead House Democrats' investigation into Trump and Russia and Trump's first impeachment, had been invited to the White House to view alleged intelligence about spying on Trump's campaign. Several months later, he would learn exactly what Trump had meant from his son-in-law, Jared Kushner, according to the book.

"You know, you do a really good job on TV," Kushner told Schiff when he appeared for testimony before the Intelligence Committee in July 2017. "I don't think your father-in-law would agree," Schiff says he responded, prompting Kushner to lean in and say: "Oh, yes, he does, and that's why."

New details about Schiff's interactions with Trump's Republican allies in Congress, the former President's aides and even Trump himself are recounted in his book "Midnight in Washington," which offers a window into the Trump presidency through the lens of the 11-term congressman who became lead impeachment manager for Trump's first impeachment in 2019. The latest in a series of books scrutinizing the Trump era from journalists, Trump insiders and the former President's Democratic critics, Schiff argues the forces that enabled Trump's rise and sustained his presidency still threaten American democracy today.

The book walks readers through Schiff's real-time reaction to some of the most consequential events of the Trump administration, like the high-stakes July 2019 testimony of former special counsel Robert Mueller after his two-year investigation into Trump had concluded. Schiff had sent Mueller a handwritten note to help convince him to appear before Congress, and he writes that it was "heartbreaking" to then see Mueller struggle to answer basic questions.

"Had I known how much he had changed, I would not have pursued his testimony with such vigor -- in fact, I would not have pursued it at all," Schiff writes.

As Mueller testified in the morning before the Judiciary Committee, Schiff writes that Intelligence Committee Democrats overhauled their strategy for Mueller's second session with them in the afternoon. "No questions calling for a narrative answer," Schiff said he told the committee. "No multipart questions. If you think your question may be too long, it is. Cut it down."

'You're really in his head'

Schiff, 61, was among the most polarizing figures in Washington throughout the Trump era. To Democrats, his efforts to show how Trump's campaign colluded with Russia were a shining symbol of the Trump resistance. He became a fundraising star for the party and even a pseudo-celebrity in Democratic circles.

But to Republicans, Schiff was a chief villain. Trump and his allies in Congress accused the California lawmaker of spreading false claims about the Russians having kompromat on Trump, and then charged that he took the country down a perilous path with a rushed, partisan impeachment ahead of the 2020 election.

It's clear Schiff's book is written for an audience already on his side. The book condemns the Republican Party under Trump as an "antidemocratic cult organized around the former president." There's plenty of jabs for the Republicans Schiff frequently clashed with: He accuses his Intelligence Committee counterpart, California Republican Devin Nunes, of spreading Russian disinformation during the impeachment inquiry and former GOP Rep. Trey Gowdy of being "more interested in protecting the president than in learning the truth." Schiff needles GOP Rep. Matt Gaetz as the "congressbro from Florida."

Schiff doesn't shy away in the book from the barrage of criticism he faced from Republicans or Trump, particularly Trump's frequent insults on Twitter. Schiff cites Trump's tweets repeatedly to show how his actions landed with the former President, a reminder of how Trump's now-defunct Twitter feed used to drive events in Washington.

"You're really in his head," Schiff quotes House Speaker Nancy Pelosi telling him after Trump attacked Schiff on Twitter in the early days of the first impeachment inquiry.

At the same time, Schiff says the frequent attacks took a toll on his family, writing about how his wife and children had to adjust to life with his security detail and a frightening episode when a man tried to open their front door at 1 a.m.

During the January 6 attack on the US Capitol, Schiff writes, Republicans told him he needed to stay out of sight as they were fleeing the House chamber, a sign of how he'd become a lightning rod.

"You can't let them see you," a Republican lawmaker told Schiff, according to the book.

'It was completely my mistake'

Schiff acknowledges missteps in the book, such as when his staff was contacted by a Ukraine whistleblower in 2019, before the whistleblower filed a complaint alleging Trump was soliciting help from Ukraine to investigate then-candidate Joe Biden. But after the complaint became public, Schiff said in an interview on MSNBC with journalist Sam Stein that his committee had not spoken with the whistleblower.

"It was completely my mistake, and I needed to own up to it," Schiff writes, saying he had asked his aides to send him Stein's phone number. "I want to call him and apologize."

Still, Schiff accuses the Republicans of misrepresenting the contact to falsely claim that Democrats helped the whistleblower write the complaint and that Schiff knew the identity of the whistleblower, which he says he still does not.

Schiff writes with particular disdain for House Minority Leader Kevin McCarthy, sharing an anecdote where the two Californians talked about the upcoming 2010 midterm elections on a plane ride back to Washington. Schiff accused McCarthy of misrepresenting the conversation to reporters, writing that McCarthy revealed how he operates when Schiff confronted him on the House floor.

"You know I said the exact opposite of what you told the press," Schiff says he told McCarthy.

"I know, Adam," McCarthy replied, according to Schiff, "but you know how it goes."

Schiff's book offers some new insights into the investigations he led, even for those who tracked the Trump probes closely. He tries to explain how his relationship soured with former Rep. Mike Conaway, the Texas Republican who in 2017 was put in charge of the House Russia investigation that became a bitter partisan feud, including text messages the committee leaders sent each other as the investigation plodded forward.

"You are trying my patience with this front running on what the committee 'might' do," Conaway texted Schiff following a 2017 television appearance, according to the book.

"And you are trying mine," Schiff says he replied. "We do need to talk. Our members are losing patience and I am in agreement with them."

'The four and the 40 million'

Schiff goes through the impeachment hearings and trial with a running commentary on the public proceedings and how Democrats were preparing and reacting behind the scenes. When the White House released the transcript of Trump's call with the Ukrainian President in September 2019, Schiff was with his staff in the committee's secure spaces. "I kept muttering the same thing, over and over," Schiff writes. "'Holy shit. Holy shit. Holy shit.' And finally, 'I can't believe they would release this.' "

Schiff acknowledges some of the tensions he had with Judiciary Chairman Jerry Nadler, a New York Democrat, during the House's impeachment proceedings, recounting a blow-up between the two committees over language in a resolution setting out the rules of the impeachment inquiry. "It was cathartic for Nadler and me to finally vent our differences and get it all out on the table," Schiff writes.

Schiff heaps praise on the impeachment witnesses who came forward during the inquiry, explaining how he and his staff weren't initially sure they would get the cooperation from the officials who illustrated Democrats' case against Trump. Schiff writes that he initially wanted witnesses to testify solo, but he was convinced by his advisers to pair them for the public hearings -- a process that involved moving around combinations on a large whiteboard.

Once they got to the Senate impeachment trial, Schiff writes, House managers knew they weren't going to convict Trump, which required a two-thirds vote. He says their case was targeted to "the four and the 40 million" -- the four GOP senators needed to get witnesses for the trial and the larger public audience that was watching.

In the end, Senate Republicans blocked witnesses, but the House managers did convince one GOP senator to vote for conviction: Sen. Mitt Romney of Utah. Schiff writes that he had a chance encounter with Romney during a break in the trial that gave the managers some helpful feedback.

"We almost bumped into each other on the way through the lobby behind the chamber, and he remarked that he was interested in knowing more about how the hold on military aid was communicated to the Ukrainians," Schiff writes.

Even as he led his committee's investigation into Trump, Schiff's role as House Intelligence chairman also put him in the odd position of offering Trump his advice -- during a June 2019 White House meeting with congressional leaders -- on whether to retaliate after Iran had shot down a US drone.

After the two exchanged pleasantries when Trump arrived, Schiff spoke up to fill a void in the Cabinet Room, praising Trump's selection of Mark Esper to lead the Pentagon.

"Mr. President, I think you've made an excellent choice for defense secretary. I've known Mark for a long time, and think he will do a fine job. I hesitate to say so, because I wouldn't want you to hold it against him," Schiff said.

Schiff wrote that the conversation moved to other matters before Trump turned back to him, asking: "Just how long have you known Esper?"

"Oh my God," Schiff writes that he thought to himself, "have I just killed his nomination?"