Oliver Stone visited Stephen Colbert’s “Late Show” Monday night and had to answer some tough questions. The director has gotten some heat recently for his four-part documentary about Vladimir Putin — “The Putin Interviews” — which airs in one-hour installments on consecutive nights through Thursday. If the glimpse so far is any indication, the Oscar winner lobbed a lot of softballs at the Russian leader and took the dictator’s words at face value.

Colbert, on the other hand, was a ruthless interrogator. In a short clip that ran before the interview, Putin claimed his country would never interfere in another country’s domestic affairs, to which Stone responded, “Thank you, sir. We’ll see you tomorrow.”

Colbert pressed Stone on the moment, wondering why he didn’t push harder.

“You have to be polite,” Stone insisted before throwing in some other facts to bolster his argument: It was a two-year deal, and Putin is a very busy man.

“But no follow up on that question?” Colbert asked. “That doesn’t seem like an interview, that seems like an opportunity for him to merely propagandize.”

Stone insisted the fourth hour will be more hard-hitting.

Russian President Vladimir Putin and film director Oliver Stone in the four-part documentary “The Putin Interviews.” (Komandir/Courtesy of Showtime)

The interview got more awkward from there, especially when the audience started revolting against Stone’s earnest responses.

When Colbert asked what about the documentary is most surprising, Stone responded, “I think devoted to his country and I’m amazed at his calmness, his courtesy — he never really said anything bad about anybody and, I mean, he’s been through a lot. He’s been insulted and abused …”

At this point groans and incredulous laughter started rising in the audience.

“Abused by the press, in the media,” Stone clarified, which only turned the smattering of laughter into a louder roar.

The director was distracted but seemed resolved to press on, even after Colbert asked if there was anything — anything — negative Stone would say about Putin. “Or does he have your dog in a cage someplace?” Colbert asked, prompting whooping and clapping.

“What is wrong with detente with Russia?” Stone asked, seemingly frustrated. “Why would you be against it? I don’t understand this mentality.”

But this is an oppressive leader, Colbert insisted, one who suppresses freedom of the press. Given Stone’s staunch views about free speech, it seems odd that he has so much compassion for a man accused of killing adversarial journalists.

“Listen, no question, he’s a social conservative,” Stone said.

More snickering.

“I don’t know why you’re laughing,” Stone said, fed up.

“Because it seems like a mild description,” Colbert explained.

Stone got the chance for one final plug for the documentary, promising plenty of questions about the American election, if only people will sit “patiently” through the four hours.

Maybe that fourth hour really will redeem him. But then he added: “Has [Putin] murdered a man? I wouldn’t know how to ask him that question. I’ve looked at the evidence, too, and if I believed it, I’d go after him.”

Hmmmm. Colbert probably had plenty of retorts, but time was up. They’d just have to agree to disagree.