“What, Grandma?”

No response.

We’ve arrived at the gates to her retirement home. I pull to the side and put my car in park. The metal dinosaur still hums reliably, despite its age. I want to see Lane’s eyes and I’m tempted to put on the inside light but decide it might feel like scrutiny. Nothing is surer to derail her. We sit shadowed by street light.

“What do you have to tell me?”

“I’m sorry,” she repeats.

“What are you sorry about?”

“I did a bad thing.”

“What bad thing?”

No response.

“Grandma Lane, you said there’s something you have to tell me.”

“It’s catching up. It’s caught up. Things from a long time ago catch up, right? Eventually.”

“I don’t know. Maybe. Depends on what things, Lane.”

“I did a bad thing,” she repeats.

She looks grave. But I’m never sure these days whether to put any value in her ramblings—or how connected her ideas are. Under the circumstances, this one bears further investigation.

“Are you saying that you did something bad that is catching up to you?”

“Well, I’m sure that’s true, Nathaniel.”

It’s a platitude. One of dementia’s symptoms is that its sufferers tend to respond with stock answers, relying on automated, practiced responses to supplant more sophisticated processing.

I reach for her hand and take it in mine. She resists for an instant, and then relents. Beneath skin withered by time and pocked with age spots, I feel strength coming from her fingers, the flexor digitorum and her other forearm muscles. Grandma’s still in there and kicking.

“Grandma Lane, please. Are you keeping a secret from me? Do you want to talk about it?”

“Don’t pester me!” An outburst.

I fall silent, hoping stillness will bring calm, lucidity. I can’t tell if there’s substance to her muttering—or continuity to it.

She looks up at the home.

“They have a fitness room and soft pillows on the couches,” she says. “But it’s strange there.”

The Manor is a castle-like structure that not only is anomalous for San Francisco’s inner Sunset District, it is indeed eerie. It looks beamed from mythical Transylvania, a cryptically imposing edifice with a spire cloaked in fog.

Its ancient façade makes its innards all the more contrary. Magnolia Manor provides retirees with the highest-tech amenities. Residents have wireless access, dozens of new computers and printers, handheld game devices. In the activities room, dozens of withered octogenarians often sit nose-to-screen playing virtual golf or talking in videoconferences with their grandchildren.

Of late, many of the residents, including Grandma Lane, are using the technology to share their life stories. They sit in cubicles and talk into microphones to record tales of the 20th century. Low-cost cameras attached to the computers capture grainy digital images of the storytellers. This project is called the Human Memory Crusade. It’s ambitious, this transferring of our grandparents’ fading memories into a database.

I drive in through the gates.

“I give up trying to get into that head of yours, Grandma. For now.”

At the Manor’s front desk, we get our first break of the evening.

“You’re lucky Vince isn’t here,” the nurse says. “You’re way past curfew.”

Vince Alito is the home’s director and autocrat. He hates me, or acts like it. He browbeats me for being an insufficiently dedicated grandson and for our family’s failure to make timely payments for Grandma’s bills, including for “extra” services, like car rides and cable television access in her room, and, of late, a bigger monthly bill reflecting her graduation into assisted-living care. She gets to stay in the same room but requires more frequent attention.

With my dad living in Denver, I’ve taken primary duty for Grandma’s care, becoming the face of the family. I’m also responsible for transferring money each month from Grandma’s meager trust to the assisted-living facility, and timely bill paying has never been my strong suit. Still, the chip on Vince’s shoulder is hard for me to understand. Once I said to him: “Usually, I don’t irritate someone that much until they’ve known me for a while.” He responded: “I’m a quick study.”

I am relieved but also a little surprised by Vince’s absence; he’s a retirement-home fixture, synonymous with this quirky, sometimes sad, place.

I take Grandma to her room. I sit by her bed and read to her from Mark Twain’s A Connecticut Yankee in King Arthur’s Court while she falls asleep. At one point, she jars awake and smiles.

“Get married and have a family,” she says. “You’re not getting any younger.”

Grandma Lane never used to give me advice—certainly not to conform. One time, she asked me to take her to a Tracy Chapman concert so she could see what all the hype was about. Just before the encore, she leaned into me and whispered that she and I were birds of a feather—“iconoclastic romantics,” she said.

Nearly a decade ago, she was the first person I told I was quitting medicine to be a journalist. I was well more than $100,000 in debt when I exchanged stethoscope for reporter’s notebook. The medical life felt too rote, black-and-white, like I was a glorified auto mechanic, performing Jiffy Lube diagnoses of the corpus. Journalism let me roll around in life’s gray areas and emotional muck.

“Question your government and your spouse. Trust your hairstylist and your gut,” she told me at the time.

But she’s right; I’m not getting younger.

At thirty-four, I’m a standard bearer for what pundits call The Odyssey. I’m exploring still, enjoying it some, not like I used to. Critics who like to see life packaged up neatly would say I’m thrilled by the chaos, using an endless search for a perfect landing spot as an excuse to not settle down. Some of those critics are close friends and family.

Physically, I’m aging more traditionally. I’m having more trouble getting up and down a basketball court. My five-foot, eleven-inch frame isn’t metabolizing snack foods the way it used to. My haircuts come less frequently. But when I have a good one—haircut—I can pass myself for my late twenties. I have a strong nose, like Grandma. Pauline, who runs Medblog, says women find me attractive because I listen. With a little carpentry, she says, I could make someone a good husband.

My phone rings.

It’s Pauline. The phone clock reads 8:52.

“I was just thinking about you,” I answer. “Your phone must be reading my mind.”

“You didn’t respond to my text. Under company rules, you can only do that if you’re dead.”

“What if I was busy avoiding death?”

“What?”

“I’ll tell you later. What’s up, boss?”

“You’ve received a mystery package.”

I don’t know what she means and I’m feeling impatient and desperately uninterested in work. I shouldn’t have answered the phone.

“It’s a manila envelope,” she continues. “On the front, it says: ‘Nathaniel Idle. For your eyes only.’ It’s written in thick blue ink and rotten cursive, the kind of penmanship you’d find on the prescription pad of a drunken doctor. Or a sober one, actually.”

She intends a joke. I don’t laugh.

“Nat, do I detect you’ve lost your sense of humor?”

She sounds hurt.

“Long day.”

“Everything okay?”

I look at Grandma. “Fine, now.”

“I’m insatiably curious about the package. There could be some incredible scoop on the thumb drive,” she says.

“Thumb drive?”

Pauline laughs. “Did I forget to mention that I opened the package? Inside is a two-gig memory stick. I hope you’re not going to nail me for mail tampering. I did it in the interest of journalism. And I was bored.”

I finally laugh. “Pauline, you are one seriously impatient quasi-journalist.”

“Birds of a feather.”

“So put the drive in the computer. See what’s on it.”

“Thanks, Hercule Poirot. I did that. It’s encrypted.”

I sigh. “What do you want me to do about that?”

“I assume you know the password.”

“Why’s that?”

She explains that when she puts the mysterious memory stick into the computer, a screen pops up with a place to enter the user name and password. She says the user name is already filled in with the words “Nathaniel Idle.”

“But the password is blank. Looks like you’re the one who has to fill it in,” she says.

I get a bad feeling. Not just because the day is definitely presenting a second strange mystery, but because only a handful of intimates call me “Nathaniel.” When I hear my full name, I know I’m in trouble—or in love.

“Come down and we’ll try to open it over a drink,” Pauline says. “What better have you got going on a Thursday night? Besides, how often does life present you a genuine mystery? I’m intrigued, and thirsty.”

I hear in her voice that playful and intense tone that makes Pauline engaging, effective, and dangerous—professionally and personally.

I look at Grandma. Is there even a remote chance that the contents of the drive could explain the shooting in the park?

I tell Pauline I’ll come by shortly and we hang up.

I think about what happened in the park. Maybe the cops are right to speculate we took potshots from a maniac. Though that doesn’t explain the phone call I received. Have I pissed someone off?

I think about the stories I’m working on. The Porta Potti piece notwithstanding, it’s hard to fathom any of them could be cause for attack.

One is a magazine piece about Stanford neurologists placing precision magnets on people’s heads to diminish chronic pain. Another pertains to research at Johns Hopkins that uses brain imaging to show that a driver using a cell phone cannot simultaneously focus both on the road and a conversation; the structure of the brain, unlike the structure of a computer chip, does not lend itself well to multitasking. A third story is about Grandma herself. The editors at Elder Care magazine asked me to chronicle my relationship with Lane as she “matures.” The story has been personally intense to report, or, rather, it was—before Grandma’s mercurial descent. Before she really devolved, our conversations about her life had given me some insight into the bond between us and her own struggles settling down as a young woman.

I kiss her on the forehead. Her eyes open and she grabs my hand, startling me.

“He’s at the dentist,” she says loudly.

“Who, Grandma?”

She withdraws her hand. She’s frightened.

“Who is at the dentist? The man in blue?”

She taps her forehead.

“He’s inside here now.”

“Grandma?”

I look her squarely in the eyes. I see the essential life in her narrow blue pupils being corroded by the glassiness of dementia. Less than a year ago, she had her full wits. I thought little of it when she returned one day from the condiment station in the dining hall with a stack of napkins but forgot utensils. It seemed only a few weeks later, she spent so long in the bathroom that I knocked on the door, let myself in, and found her holding a new roll of toilet paper, stymied by how to slip it onto the silver holder on the wall.

“Grandma Lane, I love you.”

“I love you too.”

“Who is the man in blue? Did we see him today? Maybe when we visited the dentist? Remember? Was he the same man in the park? Can you tell me?”

She slowly closes her lids.

I wait ten minutes for her to wake up. I stroke her arm. I replay the shooting. I hear the popping of bullets. I see the phantom in the trees. I sense in my memories the anxiety that comes with post-traumatic stress disorder. I feel the impotence of running and hiding. I scour the bumpy topography of my brain for clues: what had I missed? Did the car have a bumper sticker? Was it a California license plate?

Answers elude me.

I kiss Grandma one more time.

I turn off the light, and leave to decrypt a mystery package.