This story is part of the My Unsung Hero series, from the Hidden Brain team. It features stories of people whose kindness left a lasting impression on someone else.

One hot afternoon decades ago, Thea Rhiannon was driving her old Volkswagen bus down the highway. When she rolled down her window to let in some fresh air, her car registration paper blew off the sun visor and onto the floor.

She leaned down to grab it, and as she did so she accidentally pulled the steering wheel to the left. When she sat back up again, she realized she had drifted into oncoming traffic.

In panic, she overcorrected and pulled the wheel sharply in the other direction. The van rolled over three times, and Rhiannon was flung onto the asphalt.

"You were driving behind me that day," Rhiannon said to her unsung hero. "You saw the accident and stopped to help. You were there when I came to, lying in the middle of the road in shock, and bleeding from a train wreck of injuries."

Rhiannon remembers him as a man in his late twenties, with a gentle manner, a soothing voice, and kind hands. If he told her his name, she doesn't recall it. But she does remember one key detail: He told her he was a medical student.

"You stayed with me until the ambulance got there," she said. "You covered me with a blanket and gave me emergency first aid, including apparently putting a tourniquet on my left arm, above where I'd mangled it so badly."

At a hospital in Vallejo, California, an emergency room doctor spent hours removing all the shards of windshield from her arm, and gave her three dozen stitches. The next day, one of the doctors told Rhiannon that if not for the tourniquet, she would have probably bled to death before the paramedics arrived.

"If by some serendipity you see or hear this story and recognize yourself, thanks for your massive gesture of kindness and compassion," she said. "I'm sorry it took me four decades to say that."

Rhiannon also has a message for the other unsung heroes of the world, who may not realize their impact on others: "Please consider this a pay-it-forward note of appreciation," she said. "From the strangers you helped who, for whatever reason, couldn't thank you themselves."

My Unsung Hero is also a podcast — new episodes are released every Tuesday. To share the story of your unsung hero with the Hidden Brain team, record a voice memo on your phone and send it to [email protected].

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