Giuliani was 'manic' during debate prep — desperately trying to get people to watch Hunter Biden video: Jonathan Karl

Jonathan Karl's new book "Betrayal "recalls a debate prep session in which Rudy Giuliani was described as outright "manic."

In the book by Carol Leonnig and Phil Rucker, "I Alone Can Fix It," it was revealed that Kellyanne Conway and Chris Christie desperately tried to lock Giuliani out of the practice debates.

"Aides told Giuliani they would be gathering at 2:00 p.m., though they were scheduled to start at noon," the authors write. "They had tricked Giuliani by giving him the wrong time."

Michael Wolff's book "Landslide" goes into more graphic detail, explaining that Giuliani couldn't stop passing gas and is always drunk or at least "buzzed." Wolff mentioned how Giuliani was determined to get Trump to lead any question asked back to Hunter Biden and the Ukraine conspiracy theories.

WATCH: Rudy Giuliani insists 'it's not my job' to investigate election-fraud claims before making them

But Karl's book describes Giuliani as being obsessed with the Hunter Biden story.

"Watch this," Karl quoted Giuliani as he tried to get people to look at his iPad.

"But as he tried to play a video showing more evidence of Biden's corruption, the iPad froze up. He fiddled with it and tried again," Karl continues, citing Giuliani's enthusiasm to show the video. "Again, he could not get the video to play. He tried several times but never could get it to work. But if Giuliani was disruptive and disorganized, he was also saying exactly what Trump wanted to hear. And as they worked through questions, Trump kept talking about Hunter Biden, just as Giuliani had urged him to do."

"Betrayal" is on sale now.

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