John Oliver opened Last Week Tonight with a look at sacked FBI Director James Comey’s testimony about President Donald Trump before the Senate Intel Committee during the week, and Trump’s reaction to same.

The testimony got everybody’s attention, Oliver noted, when he kicked things off saying he had no doubt Trump fired him because of the FBI’s Russia investigation.

While dramatic, that statement actually was not new or controversial, Oliver insisted, reminding Trump himself suggested as much in his interview about a month ago with NBC News’s Lester Holt.

“It’s more a known fact that people choose to ignore, like ‘a pet snake is a character flaw’,” he said.

Comey said Trump’s claim he fired Comey because the FBI was in disarray and its workforce had lost confidence in him was a lie “plain and simple.”

Oliver took issue, insisting Trump’s lies never are plain and simple. But the remark was just one of many times during his testimony in which Comey questioned the president’s credibility.  At one point Comey explained to the senators why he took such careful notes immediately after a dinner with Trump, saying he honestly was concerned Trump might lie about the nature of their meeting and so thought it was really important to document.

“He is is describing his meeting with the president like a person who thought he was about to be murdered,” Oliver observed.

Asked if it is unusual for an FBI director to have a one-on-one dinner with the POTUS, Comey responded, “Yes, so much so I assumed there would be others [attending]. He couldn’t possibly be having dinner with me alone.”

Oliver guessed it was not the first time a person had been tricked into having dinner with Trump alone.

But the most tantalizing moments of the testimony came when Comey said he was not able to answer questions. When he explained why he thought Attorney General Jeff Sessions was going to recuse himself from any matters regarding a Russia probe.

“Our judgement, as I recall, was that he very close to, and inevitably going to, recuse himself” for a variety of reasons, Comey said, adding that the bureau also was aware of facts he could not discuss in an open setting “that would make his involvement in a Russia-related investigation problematic.”

“Now that sounds like a big deal,” Oliver said.

Trump notably was silent that day but sent a tweet early the next morning saying, of Comey’s testimony, ‘despite so many false statements and lies, total and complete vindication.”

“Trump is essentially claiming that he’s been vindicated by testimony he’s claiming is false,” Oliver pointed out. “At this point he’s become a walking logical paradox.”

Trump reiterated his claim at a Rose Garden press conference, prompting one journalist to ask him if he would be willing to speak on the subject under oath with Robert Mueller, who has been appointed special counsel and took over the investigation into the Trump campaign’s possible Russia ties.

“100 percent,” Trump said. “I would be glad to tell him exactly what I just told you,” he said at that presser.

“Holy shit! Trump just volunteered to testify under oath,” Oliver marveled.

“Why did Trump expose himself like that? I don’t know,” Oliver confessed. “Jane Goodall could not explain” even if she studied him for years, the late-night host joked, imagining that, after studying him for years, she would conclude that Trump is “a cocktail of insecurity, horniness and malice.” But trying to figure out which was in control of Trump would be beyond her, and she would add, “I miss the integrity and emotional intelligence of the apes.”

Most infuriating reaction to Comey’s testimony comes from House Speaker Paul Ryan, Oliver announced, whose explanation that “The President is new to this”  just “proves that you can live a normal healthy life without a spine.”