Golden Dawn members have been known to bar immigrants from churches and kick immigrant children out of playgrounds.
"Leave now, no more ball game, that's it, leave the place," one Golden Dawn member is seen yelling at a group of children on a playground in Georgousis' film. "The soil has to be replaced because of the filth. If you touch it you will get a rash. The filth of foreigners."
Recently, Golden Dawn has signaled it would like to go global, and has opened offices in Germany and Australia. A website has appeared claiming to be the hub for the group's New York City office.
"Nightline's" repeated email requests for interviews from Golden Dawn members were met with an angry "No."
"You can blame your fellow mainstream media cohorts for that, who do nothing but shamelessly slander us," one email response to "Nightline" said.
But as Georgousis' film shows, Golden Dawn sees the blame for Greece's woes spreading far beyond its shores. The party claims the economic crisis in Greece is not just caused by immigrants in Athens, but in Chicago and "especially New York," Georgousis said.
"They keep posting articles that, 'it's the Jewish capital that has brought Greece to this point, which is located in New York,'" he said.
Georgousis said not just Americans but "every logical human being" should be worried about Golden Dawn and the party's negative influence.
"They already have 7 percent [of the population] in Greece. They could get more, but imagine with the 7 percent they already have, they are causing a lot of trouble," he said.
"I think if you care about democracy, whether you are American, Greek, Israeli, German or whatever, in any place on the planet, we should stop people like them."
ABC News' Lauren Effron contributed to this report