This took place a few weeks ago at something called left forum in NYC. Here is the main video of the confrontation and Zizek's response to the hecklers. There's also this short video of him being heckled earlier in the same talk. The hecklers were apparently passing out this flyer which you see in the video, accusing Zizek of, among other things, using the term "nigger" instead of "the N-word."

Some background info: Slavoj Zizek is a Slovenian philosopher and psychoanalytic theorist known in academic circles for his arcane combination of post-Freudian psychoanalytic thought with Marxist and Hegelian social theory. Which is all just to say that he's baffling to most, and also very European.

Outside of the academy he's made a name for himself as a prolific polemicist and provocateur of the political left. There is a seemingly endless amount of youtube videos featuring this guy. He likes to rub his nose a lot when he's speaking, leading many to believe he's a coke addict, although apparently it's just a nervous tic and he can't get on stage without popping a few xanies beforehand. He rambles on a lot and tends to be very hard to follow.

Anyways, though he is a leftist, he's gotten himself into trouble before for criticizing multiculturalism, identity politics, "left liberal political correctness," the academic grievance studies industry, etc., which accounts for both his popularity and infamy. This particular confrontation seems to be inspired by some comments Zizek made on the current influx of migrants into Europe, who he maintains are not simply a fun-loving bunch of token minorities coming to provide cultural edification for self-hating liberals, but actually a diverse group with diverse motivations, some of which might not be all that conductive to the welfare of European states. For example, a few migrants seem to have shown an affinity for tenderly caressing the rumps of young German Frauleins. Typical of his brand of covert fascism, Zizek blows such incidents way out of proportion, failing to acknowledge that a firm pat on the buttocks is actually a common greeting in the Arab world. Far from being a cause of concern, such incidents ought to be celebrated as a wholesome example of genuine cross-cultural exchange.

Similarly typical of the covert fascist, Zizek is unwilling to come out and say what he's really thinking, that he wants all the migrants rounded up and sent off to internment camps. He actually has the temerity to pander to leftists, adopting the (obviously insincere) position that the migrants ought to come to Europe anyways, but rather than simply opening up the boarders and letting them in, their flow ought to be controlled by Europe's great Imperialist armies (who are no doubt salivating at the opportunity of molesting some helpless migrant woman fleeing prosecution in her homeland -- we can only guess that Zizek himself has cut a deal with the Imperialist scum to get in on the action). In short, Zizek has all but outed himself as the next Hitler, and only the jeering of brave, righteous liberals at an obscure, poorly-attended gathering for self-styled radical leftists can stop him from subjugating the entire third-world to his Imperialist, fascist, chauvinist, Eurocentric rule.

The hecklers in the video are two Taryn Fivek and Molly Klein, both of whom seem to be known mostly for getting into twitter spats with leftists they deem not leftist enough. The latter gave a talk at the same left forum two years prior arguing that Zizek very well might be a "US propaganda psyop" (seriously).