A firefighter pulled a woman who was being strangled by her seat belt from this wreckage. (Prince George’s County Fire/EMS Department)

It was a wrong turn on the way to work that took firefighter William Gressen past the beam of light piercing the dark woods along Crain Highway. At first, he thought it was illumination from a construction site, but something about it still didn’t feel quite right.

He turned around, pulled over and hiked down to an embankment through brush and downed trees. About 125 feet down, he discovered the light source.

A gold Hyundai Elantra had rolled down from the road, trapping a woman inside. Blood was running down her face. Her head was wedged between the headrest and the door. And a seat belt was wrapped around her neck.

The Prince George’s County firefighter plunged his hand through a broken window and freed the choking woman, who officials say probably would have died had he not investigated the mystery light.

On Wednesday, Briana Morrissette for the first time met the man who rescued her. In a tearful reunion, she embraced Gressen and thanked him for saving her.

Prince George's County firefighter William Gressen rescued Briana Morrissette from her vehicle, which crashed into an embankment on July 9 in Brandywine, Md. (Lynh Bui/The Washington Post)

“I was unconscious during the entire accident,” said Morrissette, 22. “I only know from stories what has happened. I never had the opportunity to see his face, to touch his hand, to give him a hug, to thank him.”

Gressen said he was not sure what he would encounter when he headed down the ravine toward the light, but he was grateful his gut told him to stop.

“I don’t know what made me go that way,” said Gressen, a 12-year veteran of the department.

He had just finished seeing his family in Calvert County on July 9 when he headed back to the fire services building in Landover, where he planned to bunk before starting his next shift. But for some reason, about 1 a.m., he accidentally took a right turn instead of a left not far from the office, sending him along Route 301 behind a slow tractor-trailer.

That’s when he noticed the light and did a U-turn to check it out.

“When I first looked, I couldn’t see the vehicle at first,” Gressen said. “I went down in the meantime just far enough for me to see, and I could see the silhouette of the vehicle.”

He saw the car had rolled to one side with the right headlight buried in the mud.

Briana Morrissette meets Prince George's County firefighter William Gressen, who rescued her after her car rolled into a wooded embankment. (Lynh Bui/The Washington Post)

He ran down, circled the car and checked a few windows before discovering Morrissette.

“I looked up, you were laying like flat,” Gressen told Morrissette during their reunion. “Your feet were up by the dashboard, your head was by the headrest, but you were wrapped in the seat belt, and it had your head hyperextended all the way to the back.”

Gressen watched for a few seconds to see whether she was breathing, but her chest didn’t rise, and she wasn’t moving.

Typically in car crashes, firefighters try not to move victims until there is a way to stabilize them, but Gressen had to make a split-second decision.

He moved her head forward just far enough to unwrap the seat belt from around her neck. Seconds later, after falling over limp and lifeless, a gasp of air heaved in her chest, and she started to breathe. Gressen called 911, and Morrissette was flown to a hospital.

She said she was on her way home to Upper Marlboro after having dinner with friends in the District. She said the last thing she remembered before the crash was speaking with her boyfriend on the phone via headset. When she awoke, she was in a hospital, where nurses were trying to calm her.

“I’m eternally grateful for what you’ve done,” Morrissette told Gressen at their reunion in Landover. “It was very courageous of you. Every day, I aspire to be that way myself.”

Morrissette’s mother was also on hand to thank the man who saved her only child, whom she raised alone after her husband died about 20 years ago.

“It’s every mother’s worst nightmare to think that a child will not make it home,” Aundrea Wheeler Morrissette said. “But when we heard the story of how Briana was rescued, I burst into tears.”

At their reunion, Briana Morrissette and Gressen discovered they share a birthday, Oct. 21. But “it’s almost like Briana has a new birthday,” her mother said, thanks to Gressen’s lifesaving work. “I can’t image what my life would be like today without my only child. She’s my only family.”

Briana Morrissette, a domestic-violence coordinator for the Charles County state’s attorney’s office, suffered a broken clavicle and scratches in the crash, injuries from which she is still recovering.

It is unclear what caused her to crash, but she is glad Gressen was there when seconds made the difference between life and death.

“I wish I could remember,” Morrissette said. “Thank God he took a wrong turn.”