Peter Strzok, the former top FBI counterintelligence official, was interviewed by Rachel Maddow. Strzok says the president is compromised, and Russia has "enormous leverage" over Trump that is financial.

The former FBI agent's new book, 'Compromised: Counterintelligence and the Threat of Donald J. Trump,' is a disturbing account of Trump and his crew.

Mueller did not investigate the counterintelligence threat against Donald Trump, and the FBI did not conduct a counterintelligence deep-dive into Trump because Strzok was forced out.

Here are a few of the highlights from Maddow's interview with Peter Strzok:

• Strzok says that, when they began their investigation, the Gang of 8 was briefed and no one objected.
• Strzok says Paul Manafort shared detailed polling data from key battleground states with Russian intelligence agent Konstantin Kilimnik to help Trump
• Strzok told Maddow that Michael Flynn lied to the FBI because the White House directed him to do so. This information sheds light on Trump's and Barr's attempts to intervene in Flynn's case

"Do I think he's a Manchurian candidate? No, I don't. Do I think he's doing things in the interest of the national security of the U.S. because of all the things Russia holds over him that he doesn't want known? Absolutely I believe that. If you step back, if you look at that as a patriot, as an American citizen, it's horrifying! But it exists, and it's real, and it's something that every American should be concerned about."

Before the interview, Rachel Maddow read from 'Compromised', and it's terrifying. This book sounds like a must-read before the election.