It’s 1979 and a phalanx of military helicopters cut through the skies over Seoul carrying President Park Chun-Hee to his secret destination. Suddenly, a crisis: The shipment of virility-promoting seal testicles has not arrived. Oh well, President Park says, let’s have a party tonight anyway. So begins “The President’s Last Bang,” the true story of the last night in the life of President Park before he was assassinated by his minister of intelligence, Kim Jae-Gyu (Baek Yun-Shik).

“The President’s Last Bang” is the kind of movie Oliver Stone hoped “Nixon” would be: bomb-throwing, assumption-destroying, deeply entertaining political art. It is the most controversial movie ever released in Korea.

When Kim, the head of the KCIA (Korean Central Intelligence Agency), put a bullet through the brain of President Park, it was only the most outward symptom of his internal dissolution. Driven insane by a gimpy liver and the inability to have a bowel movement, he’s less a savvy conspirator than a holy madman.

With this film, director Im Sang-Soo has unleashed the kinkiest, funniest take on presidential assassinations since Stephen Sondheim’s “Assassins,” and he treats the last night of Park’s life as a trip through a bawdy fun house.

Gliding and sliding on little cat feet, the camera slithers through the presidential safe house, poking its nose into conspiratorial conversations, hiding around corners, eavesdropping on plotters, and, finally, flying up to the rafters as a bullet spreads Park’s gray matter across the dinner table. Anchored by a Klaus Kinski-worthy performance from Mr. Baek and with Han Suk-Gyu playing a foul-mouthed bodyguard who knows how to get things done when the chips are down, this pitch-black comedy rips into history like a shark going after a raw steak.

“Western people sit back, laugh, and enjoy this film,” Mr. Im said. “But in Korea nobody laughs. Most of them were sobbing at the president’s funeral.”

The movie is a bawdy, kinky historical romp that holds nothing sacred. But, Mr. Im said, “I think this film is a very serious film. But you may find it silly. I think that no matter how serious our lives are, they still contain these stupid things.”

The trial of the conspirators who shot Park was open to the public, and Mr. Im has based his movie on meticulous research. “I changed very small things. But what you see in my film is what really happened. That’s the reason why they are very furious with my film. Because I say it’s true,” I said.

The “they” is Park’s daughter, Park Geun-Hye, the leader of the opposition party in Korea. When she heard about the movie she went to court and was granted an injunction that forced the producers to remove documentary footage of student protests at the beginning of the film, and footage of the president’s funeral at the end. CJ Entertainment, the film’s distributor, had been hyping the movie as their big prestige picture for the year, but as soon as the studio heard the film was causing a ruckus, they abandoned it, two days before its release date.

“That was tremendously painful to me,” Mr. Im says. “But I’m appealing the decision and I’m determined that one day I’ll win.”

The most incendiary aspect of the movie will be lost on many Americans. Japan ruled Korea for 35 years, and Park was once a Japanese army officer who hunted down the Korean Independent Army in Manchuria.

Park’s love of Japan will just seem like a bilingual quirk to Western viewers, but to a Korean audience, every word of Japanese he speaks is like a red-hot poker in the eye.

But Mr. Im isn’t out to redress old wrongs. “I don’t want to frame or blame Mr. Park – this happened 25 years ago. I just want to depict a way of thinking where every relationship is based on hierarchical power, and the solution to every problem is force,” he said.

“I recently saw ‘The West Wing’ on television, and all the characters are so decent, so sincere, it’s like a child’s fantasy. But I ask Americans, is your current administration more like ‘The West Wing’ or more like my movie?”