“I don’t know if you know this,” Stephen Colbert told his Late Show guest Tuesday night, “but you’ve got a fascinating story to tell.” Considering his guest was former F.B.I. director James Comey, that might have been the understatement of the year.

During a full half-hour sit-down, Colbert chatted with Comey—over paper cups of pinot noir—about topics ranging from why the former F.B.I. director wrote his new book, A Higher Loyalty, to his shocking dismissal; the way Comey handled the investigation of Hillary Clinton’s private e-mail server; and, of course, the president’s derogatory tweets about him. That last subject prompted the biggest laugh of the night: when Colbert asked Comey about missives in which the commander in chief has called him, among other things, “slippery,” Comey quipped, “I’m like the breakup he can’t get over.”

“I’m out here living my best life,” Comey added. “He wakes up in the morning and tweets at me!”

Colbert maintained a friendly vibe with Comey throughout their interview, but he also pressed the former F.B.I. director when necessary—especially where the Clinton e-mail investigation was concerned, as well as some of the former F.B.I. director’s comments about Loretta Lynch. It was a constant high-wire act, balancing “pee-pee tape” jokes with tough questions. As with most late-night interviews, the sit-down mostly explored well-trod topics—but still, the result was interesting, entertaining, and not overly gentle. Especially compared to Colbert’s early Late Show interviews—which, remember, happened just a few years ago—the Comey chat was a great showcase for how far the host has come. The Late Show emcee was poised, charismatic, and focused on Tuesday—fair, but not too gentle.

Comey, too, resisted the urge to stick only to Trump-aimed zingers. When asked what motivated him to write a book, Comey said that he thought it would be valuable to lay out “a vision of what ethical leadership looks like—and show people, through a series of stories, how ethical leaders make hard decisions. And it would be particularly useful now when our president is not that.” Unsurprisingly, when Colbert asked Comey whether he thought Trump might be able to turn his presidency around and become an ethical leader, Comey was not optimistic.

“He’s somebody who doesn’t appear to have external reference points in his life,” Comey said of the president. “Ethical leaders make the hardest decisions by looking at some external reference point—whether it’s a religious tradition, or history or logic or philosophy. Tradition. And as far as I can tell, his reference point is entirely internal: ‘What will fill the hole in me and get me the affirmation that I need?’”

As for the fate of the country as a whole, however, Comey took a sunnier view. “Although I see Donald Trump as a forest fire—he will do great damage to our norms—forest fires allow things to grow that couldn’t grow before,” Comey told Colbert, referencing a passage from his book. “I see kids getting energized. It’s inspiring to see kids in the wake of Parkland out there getting involved. I see all parts of civil society—the media, the courts, even Congress starting to get off its rear end. I see parts of this country being energized that haven’t been energized, frankly, since the last great forest fire, which was Watergate. And so I’m optimistic that this country’s values are strong enough that we will not only survive this, we will thrive and re-balance ourselves in the wake of this.”