Once Upon a Stranger summary

Gillian Sandstrom had just gotten divorced. And she was in the mood to reclaim something she’d suppressed throughout her marriage: her love of classical music. So she drove six and a half hours by herself to a classical music festival in Massachusetts, and on her first evening, decided to climb a war memorial tower to watch the sunset. That’s where she met Floyd.

She wasn’t yet in the habit of talking to strangers, but something about the view made it feel natural. He had a book in his hand, so she asked what he was reading. One thing led to another, and when Floyd mentioned he was going hiking the next day, she invited herself along. It turned out to be a five-hour hike –⁠ far more than she’d bargained for. But by the end of it, she felt something she hadn’t felt in years: truly accepted for who she was. She never saw Floyd again.

“If you were both to die at the same time, who would you like to raise your children?” Not exactly the kind of question that inspires a career epiphany. But that’s exactly what happened to Sandstrom –⁠ then a twentysomething computer programmer sitting in a lawyer’s office, drafting a will she didn’t really need yet. While squirming in a stiff chair and trying to take her own mortality seriously, she noticed the lawyer’s diploma on the wall and made a casual remark about it.

What came next changed everything. The lawyer proudly shared that she’d only recently entered law –⁠ in her fifties. That single, offhand revelation cracked open a door Sandstrom hadn’t even realized she’d been standing in front of. She’d spent a decade in tech and couldn’t imagine walking away. But suddenly, someone had handed her a missing puzzle piece –⁠ proof that reinvention was possible. That chance encounter eventually led Sandstrom to return to school, earn a PhD in psychology, and build an entirely new career studying the science of human connection.

When Gillian Sandstrom left behind her decade-long career as a computer programmer to start a master’s in psychology, she felt like an imposter. She was ten years older than most of her classmates and unaccustomed to big cities like Toronto. Then, gradually, something shifted. Each week, walking between buildings, she’d pass a hot dog stand. One day, the woman working there smiled and waved. Sandstrom smiled and waved back. That was it –⁠ no conversation, no names exchanged. Sandstrom never bought a hot dog, even once. But from that moment on, something small and important happened: she felt seen. If the hot dog lady wasn’t there on a given day, things felt subtly off. Her presence and recognition had woven Sandstrom into the fabric of campus life.

These small interactions might seem trivial, but they’re not. In a study Sandstrom later designed, she asked customers at a Starbucks to chat briefly with the barista while ordering. Others were told to be efficient: have their money ready, skip the pleasantries. Customers who had chatted came away in a better mood and feeling more connected than those who didn’t. 

At a psychology conference in 2019, Sandstrom did something that would have been unthinkable to her younger self: she raised her hand in a room full of strangers and asked a question. Later, she walked up to the speaker, introduced herself, and cheekily hinted that she’d love to give a talk at his university. Two years later, that chain of small, uncomfortable acts led to a job offer running the Sussex Center for Research on Kindness. And none of it would have been possible if she hadn’t spent a decade talking to strangers.

Sandstrom calls this cumulative transformation a “skeleton key” –⁠ a single tool that can unlock many doors. Talking to strangers builds social confidence, helps us get more comfortable with rejection and uncertainty, teaches us to notice the world more clearly, and gradually shifts how we see other people. These benefits don’t arrive all at once. They accumulate, conversation by conversation, like interest building in an account you barely knew you had.