In our hyper-connected and gadget-bound age, the idea of living happily without possessions or email is almost subversive. And beneath the deceptive lyricism of her prose, Cara Hoffman has long shown a healthy fascination with upending the social order.

“People think they need things. Money or respect or clean sheets. But they don’t,” Hoffman writes in “Running,” her haunting and wistful third novel. “You can wash your hair and brush your teeth with hand soap. You can sleep outside. You can eat whatever’s there.”

The speaker of these words is Bridey, a parentless teenager from Washington state, surviving by guile and wit in late-1980s Athens with little to her name but the matches, lighter fluid and electrical tape she stores in her backpack. Bridey lives with two British expats: Jasper, a disaffected Eton dropout, and his lover, Milo, a poet from the projects. They occupy the top floor of a shady motel where, in return for free accommodations, they work as runners, beckoning weary tourists to book one of the grimy rooms below.

According to press materials, Hoffman herself lived similarly in younger years, getting by as a runner and taking notes for what would become this novel. No surprise. Her observations have the keen immediacy of lived scenes, similar to drawings sketched from life.

But her story, which proceeds along two tracks — one past, one present — is somewhat more fantastic. Mostly it concerns a moneymaking scheme that inadvertently links Bridey, Jasper and Milo to a terrorist plot in which several innocents are murdered. Those memories echo still in the mind of Milo who, 25 years later, has become a famous poet and teacher in New York City but cannot shake those days. Constantly, compulsively, he searches the streets and the internet for Bridey, lost to the fog of a disappeared time.

As the plot intercuts between Milo’s present-day and Bridey’s pre-internet 1980s, Hoffman’s portraits show just how revolutionary it nowadays is to live outside the norms of commerce. Milo’s students write poems about text messaging. But their lonely professor can’t keep himself from sleeping with young drifters in the park, on the sidewalk — as if trying to find his way back to a more romantic, less encumbered time.

After her well-received first novel, “So Much Pretty,” came out in 2011, Hoffman was once or twice chided for verging into screed — particularly about misogyny. She is no less fierce today but has become subtler in her statement-making, if sometimes guilty of presenting secondary characters as sketches, like Navas, a favorite student of Milo’s who is black, brilliant and, of course, different from the others; and Declan, a tattooed IRA mercenary fond of head-butting those who irritate him.

An interest in violence — particularly the political and institutional variety — echoes through much of Hoffman’s work. But here, the main actors are street kids, and Hoffman writes about their makeshift family with deep affection for the outsider.

“It’s the damage they love, really,” observes Jasper of the tourists flooding off the Athens trains to gawk at the crumbling evidence of a lost world. “They say it’s the history, but it’s the damage. No one would care in the least if these things were new — covered with gaudy, bright primary colors like it was back then. They love the ruin.”

The same could be said of Hoffman.