It was April 29, 2015, and Rachel Hall was biking through Temple University's campus, in that blissful, liminal space between finals and graduation, where the phrase "the rest of your life is ahead of you" is, for once, not a cliché.

Behind her was a double major in sociology and criminal justice, and four years of playing goalkeeper for the women's lacrosse team.

Ahead was a spot in the District of Columbia police academy and a career in law enforcement.

The car hit her at 13th and Diamond Streets. She flew over the hood, over the roof, and crashed to the pavement. Her St. Christopher medal was wrenched from its chain and bounced into the street.

A few days later, with Hall lying in a coma at Temple University Hospital, her father and brother went back to the intersection. Something glinted against the asphalt.

It was the St. Christopher medal, battered but whole. They brought it back, put it on a new chain, and gave it to Rachel.

She has worn it all year, through months of grueling rehab, as she has learned to walk and talk and eat again.

She wore it Thursday, when she walked, at last, at Temple's graduation.

Here is what Kathy Hall remembers: The phone ringing in her Mullica Hill kitchen. On the other end, Temple's dean of students telling her there had been an accident. Hit and run.

As of 7 p.m., Rachel was still alive, the dean said. But now it was 8. Kathy ran into the living room, where her husband was sitting, and screamed at the top of her lungs.

At Rachel's bedside at the hospital, her mother counted the days. Two days, three days, four - her daughter was unconscious, unresponsive, hooked up to a ventilator and given a 20 percent chance of survival. And even if she survived, doctors warned, Rachel had suffered a traumatic brain injury. There was no telling how extensive the damage was.

Kathy squeezed her daughter's hands and waited for her to squeeze back.

Nine days. Kathy attended graduation in her daughter's place, got the diploma framed, and hung it in her hospital room. She wanted it to be the first thing Rachel saw when she woke up. She wanted Rachel to know that the rest of her life was still ahead of her.

At 35 days, Kathy wrote on Facebook from Magee Rehabilitation Center, where Rachel had been transferred: "Rachel is starting to show a low level of consciousness."

At 361 days: "If you were to see Rachel in critical condition a year ago, you would never expect her to be in the condition she is now. I am pleased to announce that Rachel . . . will be walking in graduation at Temple University."

Here is what Rachel Hall remembers: Where am I? And then, Why am I in the hospital? What has happened to me?

"I was like, 'Why am I in a wheelchair? I'm not paralyzed,' " she recalls. "I was just trying to make sense of everything."

She had a feeding tube and a breathing tube and a neck brace. At first, she practiced swallowing ice chips, then graduated to broth and finally regular hospital food.

The elite athlete learned to walk again, wobbling so much at first that Kathy nicknamed her "my little Weeble," after the children's toy - as in, "Weebles wobble, but they don't fall down."

She learned to speak through vocal cords gashed by the tube that had kept her breathing for months.

Now in speech therapy sessions, in her rush to get better, she practices the art of slowing down. Her speech therapist, Michelle Valente, has her speak into a text-to-speech app.

Rachel leans toward the microphone, takes a deep breath, and reads from the page in front of her. The text is one she's been practicing for weeks. It's one she studied in criminal justice classes before the accident, and would have recited in the police academy, one she expected to have been saying on the streets of Washington.

"You have the right to remain silent," she says, slow and loud and clear. "Anything you say can and will be used against you in a court of law."

In physical therapy at Independence Neuro-Rehab Center in Cherry Hill, Rachel does squats while balancing on a half-ball. A therapist stands behind her, hands hovering at her hips. "Be ready to catch me," Rachel jokes.

"She's doing things I didn't think she'd be able to do. Ever," says Tracey Bejusiuk, who works with Rachel three days out of the five she spends in physical therapy each week. Bejusiuk gets tired just demonstrating the exercises she puts Rachel through - hopping up and down on a step deck, doing lunges and squats with a medicine ball.

"She is a model for what we have to do with brain injuries," says Joan Roush, the center's senior vice president for outpatient services. "I have 35 years of experience with head trauma, and Rachel is remarkable."

Afternoons bring more workouts, across the river at a Magee outpatient facility. The aim is not just to regain balance or restore muscle mass. It's to pass the D.C. police academy test again.

Her trainer at Magee, Ian Crosby, has modified a workout to mimic the test. Now, with a harness around her waist to catch her if she loses her balance - rare these days - she sprints back and forth across the room.

"I was in shape to do all that, and now things have changed for me, obviously," she says, sweaty but upbeat. "But I can't compare myself with my old self anymore."

The big goals are still firmly in place: The police academy and a place on D.C.'s force. Maybe one day, a higher-level job in law enforcement, one that deals with combating human trafficking, a passion that she nurtured all through college. She was drawn to the idea of helping women in trouble.

"I feel terrible. All I want to do is help people," she says. "And I can't now. And I would have been able to."

Rachel tries not to think about this too much. There are little goals, too - ones she can accomplish in rehab tomorrow, or the next day, or next week if she pushes hard.

She busies herself with what's at hand and what's ahead. On the day the man who hit her was sentenced to 111/2 to 23 months in prison, she got a rescue dog, a 10-year-old Jack Russell terrier named Sarah. On the anniversary of her accident, she went to a Phillies game with her friends. When she's frustrated, she reads the cards and letters that supporters have been sending to her post office box since the accident. She treasures a message from her high school volleyball coach, Deana Moore.

"Tough times don't last," Moore wrote on a postcard early on in her recovery. "Tough people do."

Seven hundred and fifty graduates from the Class of 2016, and one from the Class of 2015, filled Temple's Liacouras Center.

The assistant dean rattled off a list of notable students - an older man completing his degree after 29 years; a whiz kid graduating at 21. And someone who had missed last year's graduation, who had "fought her way back" to walk today.

You could glimpse her in the audience, grinning under a mortarboard decorated with her old lacrosse number. She waited as name after name was read and students shuffled to the front.

Then she straightened her cap and her sash and her spine and got in line for the stage.

"Rachel A. Hall," the dean said. And Rachel Hall walked.

awhelan@philly.com610-313-8112

@aubreyjwhelan