HANDS-ON: Bazar (bottom) noted that once harshly enforced laws against public affection are now widely ignored. Scott Peterson/Getty Images (top) Courtesy Emily Bazar (bottom)

My dad can’t go too long without his tea. Like most Iranians, he drinks his first cup of chai with breakfast, his last before retiring and several in between. And so, after a chilly morning exploring the snow-covered, central Iranian city of Esfahan, it was time for my dad’s next round.

I consulted my guidebook, which directed us to an “idyllic” teahouse on the 340-year-old Chubi Bridge—one of several historic bridges that straddle the gleaming Zayandeh River. “Anyone can stop in at the cosy teahouse,” the guidebook said, “which some consider the best in the city.”

My guidebook had it wrong: not just anyone can stop in.

As we approached the entrance, a teenage employee working outside looked at me then addressed my father. “Families not allowed,” he said.

Families? My dad, who speaks Farsi fluently, asked for clarification. Again, the young man looked at me. “Families not allowed.”

What he really meant was “women not allowed.”

This was the sixth day of my first trip to Iran—my parents’ birthplace—and thus far I hadn’t butted up against any major gender restrictions. Sure, I was required to observe Islamic dress, but I hadn’t chosen the head-to-toe covering known as the chador, as some Iranian women do. My version consisted of a formless black trench coat over jeans and sweater, and a scarf over my hair. Next to the hordes of fashionable women wearing spiky heels and jeans rolled above their ankles, I looked frumpy.

Our standoff at the teahouse was another matter. Angry and slightly disbelieving that I was being barred from a business because I was female, I nevertheless had few options.

It was time to leave.

I was tempted to give in to the stereotype I had so long resisted—that of Iran as a repressive, male-dominated society. But as my father and I approached the next span on the Zayandeh—the exquisitely tiled Khaju Bridge—the stereotype dissolved. We were walking into a case study of modern-day Iran’s contrasts and complexities.

The Khaju teemed with people, young and old, male and female. One seemingly ordinary scene amazed my father: a young man and woman in their late teens walking hand in hand along the pathway beside the bridge.

This was an audacious act because the couple wasn’t married. Iranian men and women are prohibited from public displays of affection unless they are spouses or close relatives. Such a transgression can lead to fines, jail time or beatings at the hands of the Basij, a religious militia that views itself as defender of the Islamic revolution and enforcer of moral values. During his last visit to Iran 13 years ago, my father told me, he never once saw a couple—married or otherwise—holding hands in public. Doing so surely would have caught the eye of a zealous Basiji, who would have questioned the couple and possibly hauled them off for punishment.

Twice in the same Tehran restaurant, a Basiji told my aunt to hide wisps of hair that had fallen from underneath her scarf. Another time, Basij faithful stood at the side of the road wearing fluorescent traffic vests, waving down cars to search for “suspicious” cargo. But on this day, the Basijis were nowhere to be seen. This was a vast improvement over the past, our family and friends explained: not only were Basijis less prevalent, their punishments were less severe as well.

What I observed in Iran was fast and furious social change, fueled by the spread of technology and the potent force of youth. Young men and women make up an increasingly influential segment of the Iranian population. Two-thirds of the country’s 70 million people are under the age of 30.

Three of my cousins are telling, but typical, examples. Shiva, a glamorous 22-year-old, always had one hand on her cell phone, arranging get-togethers with her male and female friends by text-messaging them in “Pinglish” (Persian words written with English letters). Pedram, 23, after visiting the local “coffeenet” for cyberspace dates, watched risqué Enrique Iglesias videos beamed into his home via satellite. Farrokh, 21, served as deejay at a party where dancers grooved to thumping techno beats.

Across the country, young Iranians are fashioning creative ways to skirt the restrictions placed on them. The most obvious example is dating. Though it’s officially banned, the practice is rampant in portions of northern Tehran, where well-to-do teens flock to trendy malls that serve pizza alongside kabobs. There, I met 21-year-old Pooya, who stared at a woman sitting across the Jaam-e-Jam food court for an hour, “working on her” with his eyes. Every so often, to complement his stare, he cocked his head suggestively to the side.

Though the woman was sitting with a man, Pooya was convinced she was returning the signals. When she got up to leave, he jumped up and casually walked past her, hoping she would give him her phone number—or ask for his.

It wasn’t meant to be.

“Sometimes you give out 20 numbers, and maybe no one will call,” said Pooya, whose neck smarted from the hour-long exercise. “There are so many young people who don’t have a place to go. Our only remedy is to come sit here and pick each other up.”

The level of flirtation escalates outside the food court, where cruising SUVs and Peugeots jam the tree-lined Valiasr Avenue. Cars full of women wearing nail polish and furs, cell phones plastered to their ears, creep past cars full of men blasting Persian pop music recorded in the United States. Phone numbers are tossed on pieces of paper from one car to another.

All around us, as they did that day on the Khaju Bridge, Iranians were gleefully breaking rules. Amid the din of laughter and flirtation, the Chubi Bridge teahouse seemed distant and peculiar.

Another revolution may be under way.