Yehonatan Indursky showed me around Ponevezh Yeshiva one evening in January. Known in Israel as “the Harvard of yeshivas,” Ponevezh sits perched on a hill above the ultra-Orthodox city of Bnei Brak. We stood at the back of its vast central study hall. Hundreds of white-shirted teenagers and young men packed the room, hugging the lecterns where their leather-bound Talmudic volumes lay open, the holy texts close to their chests, as if the ancient words could be absorbed not only by their minds but also by their bodies.

Two decades ago, Indursky was one of them. Tzitzit, the specially knotted tassels a reminder of his relationship with God, dangled at his hips. He was eager to have me see this exalted school, where he had lived and studied. But certain things didn’t look exalted. Except for the gilded aron kodesh, the structure where the Torah scroll is housed, the main study hall was unadorned. The bulbs were bare, maximizing their harsh fluorescent light. The floors of a corridor and study nook were strewed with litter. On the grounds outside, we passed a decrepit refrigerator sitting like forgotten junk. The Haredi, or ultra-Orthodox, Indursky said, “are less conscious of superficial things.” Even the dishevelment held spiritual devotion.

At Ponevezh, Indursky had dedicated himself to the Torah and Talmud during nearly all his waking hours. But then, when he was 18, he fled the yeshiva. He fled his family. He shed his kipa and high-sitting wide-brimmed black hat. He cut off his payos, the long sacred locks that grew from his temples.

He fled — and eventually created “Shtisel,” a television series delving into the world he abandoned, a deeply layered portrait of a Jerusalem family cloistered within Haredi society. And though its niche subject, delicate stories and quiet tone might have doomed it to drift into oblivion, the show was a hit when it debuted in Israel in 2013. For the first of its three seasons, it won 11 Israeli Television Academy Awards, including for best drama series and best drama screenplay. In Israel, The Forward reported, “Shtisel” was everywhere: “Huge billboards featuring the show’s bearded and side-locked characters popped up in secular Tel Aviv, a city where it’s more usual to see images of bikini-clad supermodel Bar Refaeli looming over the freeway.”

In the United States, the show was a surprise phenomenon when Netflix brought it here five years later. What came to be known as “Shtisel mania” spread across Jewish communities throughout the country; a pair of events at the Streicker Center at Temple Emanu-El, a Reform synagogue in Manhattan, sold out within hours, drawing more than 4,500 fans.

In both countries, the show’s devotees included the Haredi. Despite the ultra-Orthodox ban on television and the blocks installed on their devices to prevent most internet access, many found a way to watch the series. Rigidly isolated as the Haredi are, Indursky said, there are always people in the community ready to assist with working around media restrictions. Indursky’s father, a retired copy editor of religious texts, told me that when “Shtisel” appeared, he was asked by a worshiper at his Jerusalem synagogue, “What is it with your son that he does shame to the community?” But this was the minority view. “The Haredi were excited,” Indursky’s father said. “A lot of people asked could I get them CDs.”