No Western musician has been given permission to play concerts in Iran since the country's Islamic Revolution of 1979.
This week marked a watershed then, with German electronic musician Schiller bringing his pulsating beats to awestruck audiences in the capital Tehran.
"I couldn't believe it when I heard Schiller was going to performing in Iran," said Arash, a 22-year-old student who declined to provide his last name. "At first I thought my friend was joking, there is no way they are going to give permission for Schiller to perform here, but they did. This is so amazing!"
Despite the enthusiasm, the event was still a peculiarly subdued affair.
Security officials patrolled the aisles with green lasers to check women's headscarves had not fallen around their shoulders, they ensured there was no fraternizing between the sexes, and the audience was prohibited from any dancing.
Although not widely known in the United States, Schiller, whose real name is Christopher von Deylen, has sold more than 7 million albums worldwide.
He was originally scheduled to play two concerts in Tehran this week but after the $40 tickets sold out within hours, three more nights were added to the trip.
"We heard about it by word of mouth," said Arash's friend, 27-year-old Farhad. "The first three nights were sold out but we managed to get two tickets for the third night."
For Iranians lucky enough to bag a seat it was a once-in-a-lifetime opportunity to experience live Western music in their strictly conservative society. The decision to allow the event also mirrors reforms by Iran's arch rival, Saudi Arabia, which has recently brought back concerts, movies and other forms of entertainment.
But at the performances in Tehran this week not all rules went out the window.
The five concerts took place in a 3,000-seat auditorium at the Ministry of Interior, but the evenings felt more like a trip to the movies than a performance of live electronic music. The audience didn't dance and barely got out of their seats as Schiller pumped out rhythms that spark euphoria across the nightclubs of Europe.
In fact, in Iran there was no dance floor at all.
Kamran, 26, said that when Iranian bands play in the capital, audiences sometimes defy these regulations and stand up to dance. But that didn't happen here, he said, because the crowd didn't want to jeopardize the chances of other Western acts being allowed to come to town.
"It was still a fantastic experience, worth every penny," he said.
Von Deylen, who has been performing as Schiller since 1998, was not put off by the unique reception. He said none of his concerts had sold out as quickly and that he found the entire experience humbling.
"The audience reaction is so pure, genuine and very open," he said. "The energy we get from the audience, now three nights in a row before we even play a single note, is 10 times more intense than we are used to getting after a concert in other places."
Rather than dancing and cheering, the crowd showed its appreciation by breaking out into chants of "well done," "we love you," and "don't go, Schiller," before giving him a standing ovation at the end of the show.
The first Western act to perform in post-1979 Iran was almost the British-Irish singer Chris de Burg, who has an unlikely cult following in the country. In 2008 he obtained a permit to sing here, but conservative clerics vetoed the event and the concert was cancelled at the last minute.
Lots of Iranians who spoke with NBC News said they would like to see hard rock or even heavy metal if there was a repeat of this week's softened rules.
"I hope there will be more concerts in Iran, maybe some hard rock," said 24-year-old Pegah.
Schiller certainly advises anyone to go to the city, even if it's not to play music.
"Go there! Go there even without a concert," he said, adding that concerned messages from his friends and family before he traveled were overblown.
"I got a lot of messages telling me to be careful and, 'I hope you will be safe and please come back in one piece and please don't let them hang you'," he said. "Whatever."
