Critical mass: (physics) the amount of a fissionable material necessary to sustain a chain reaction at a constant rate.

—Nuclear Chemistry Flash Cards Emma Haverford Never Threw Away After Undergrad

Most people are familiar with critical mass. If not the physics concept, then in the figurative sense. Critical mass is when someone reaches the end of her rope, when the straw breaks the camel’s back, when she simply can’t take it anymore.

Critical mass is when shit gets real.

For me it started at around seven a.m. Saturday morning, when Dylan Hunter swaggered into my favorite coffee shop wearing a pair of faded jeans that hugged his muscled thighs, leaving nothing about his drool-worthy body to the imagination. The man is built like a Greek god or a superhero or one of those guys who enter lumberjack competitions for a living. He’s preposterously good looking, a head-turner no matter what your sexual preference.

Gay, straight, bi, not-all-that-interested-in-nookie-at-this-life-juncture-thank-you—it doesn’t matter. When a man with that kind of raw animal magnetism passes by, you can’t help yourself.

You turn, you look, maybe you drool a little if you didn’t sleep well the night before and are having trouble controlling your body’s involuntary responses.

And even though the way he teases me like the new girl in school who swooped in to steal his Star Student award drives me up the wall, his sleepy hazel eyes and crooked smile work their dark magic the way they always do. Even as my lips are saying all the right things—sassy, confident things that prove I’m not about to let this man bully me into backing away from something I want—I know my eyes are saying something entirely different.

My eyes are making invitations that haven’t been cleared by my brain or my heart, while tingling sensations race across my skin and something deep in my core yearns toward Dylan like a moth to a flame.

But we all know what happens to the moth when it finally scores a hug from fire, right?

It burns. It suffers. And then it dies. Bye-bye moth, better luck next incarnation. Hopefully you’ll be born with a better sense of self-preservation.

Luckily, I am not a moth.

I am a woman who knows better than to mess with men like Dylan.

I snuff out the yearning with another shot of espresso, get my oatmeal to go, and ignore the way the morning sun glints off Dylan’s sandy blond hair as he laughs at something the man next to him—his brother, I think, though we haven’t been introduced—is saying.

I moved to Sonoma County to embrace the beauty of life—real life, not the virtual existence I’d been sleep-walking through for years—but some beautiful things are best observed from afar. No matter how lonely my evenings have been, the last thing I need is a fling with a commitment-phobe who thinks I’m Satan’s handmaiden and hasn’t been in a long-term relationship since his senior year of high school.

Bless small town gossip for keeping me in the know.

I’m sure it will come back to bite me on the butt sooner or later, but so far, I appreciate getting the scoop on my new neighbors. It’s like a map marking the safe path through a minefield of interpersonal relationships going back generations. As the new girl in a small, small town, I need all the help I can get.

On my way out of Barn Roasters, I pause to hold the door for a young mother with a stroller, and the baby—an angel-faced little boy with oodles of dark curls—flashes me a gummy smile.

The yearning I thought I’d smothered with espresso blazes to life again, even fiercer than before.

It’s different than the pull toward a beautiful man, but it springs from the same source—from the need to connect, to create, to love and be loved. It springs from the river of emotion damned up deep inside of me, desperate to be set free to flow out into the world.

Less than a year ago, I was positive a baby was in my future. My near future. I had an engagement ring on my finger and a chart on my bedside table tracking the days when I was most likely to conceive. Jeremy and I joked about being rebels, bucking tradition and going for baby-makes-three before we walked down the aisle.

Later, he would tell me that I was already married to my job. That the seventy hours a week I spent writing code for a top Internet search engine was the reason he didn’t want to set a wedding date, the reason he wanted to get me pregnant, so I would be forced to slow down, the reason he eventually had an affair and left me for another woman.

Now, I don’t know if I’ll ever have a husband or children.

Though, at this point in my life, it’s the loss of those dream babies that cuts a hole in my chest the size of the prize-winning pumpkins in Farmer Stroker’s patch. I ache for them in a way I’ve never ached for anything, proving you can be haunted by something you’ve never had.

The thought follows me back to my house on the edge of my new property’s ten-acre vineyard, making the silence I usually appreciate feel like a portent. I will always be alone, in silence. There will never be a voice calling out to welcome me home, or a child’s laughter in the garden, or any of the family sounds I remember from my early years, that golden time before my parents’ split and my sister Carrie and I became painful reminders of what they had lost.

I shower, change into clean clothes, and grab my backpack full of worksheets and today’s lesson plan, determined to buck up and enjoy the rest of the day. But despite the early autumn sun warming my skin and the smell of squishy blackberries fermenting on the vine perfuming the air as I ride my bike to the elementary school, my worldview remains gloomy.

My two-hour weekend class, Cool Girls Code, allows me to put my old life to use enriching my new one, helping the next generation of girls confidently take their place in the computer science field. So far, I’ve been working with ten girls, ages five through fifteen, and they are all lovely, intelligent, sweet, and curious ladies who make me feel hopeful about the future.

But today their smiles and laughter, their victory cries and groans of frustration as a line of code that worked in the command window fails to run inside the function, don’t warm me in the usual way.

Instead, they are fingers probing a bruise, reminding me where it hurts.

It hurts right there, in the center of my stupidly lonely heart. And when seven-year-old Isabella gives me a hug on her way out the door—telling me that she’s going to bring me some of her abuela’s homemade tortillas next week for our lunch break—it’s all I can do not to break down and cry.

Yes, I nearly start weeping in front of my shiny, happy students. So I do what any self-respecting woman would do—I grab a bar of gourmet dark chocolate from the farmer’s market on the way across town and eat the entire thing. Screw keeping my caffeine and sugar consumption under control.

Desperate times call for chocolate-intense measures.

I arrive at my two o’clock doctor’s appointment with my blood buzzing, which unfortunately does nothing to make my annual lady parts examination any less uncomfortable. Dr. Seal seems like a kind, compassionate woman, but I would swear she pulled that speculum out of the deep freeze seconds before I arrived.

The exam room is freezing, too, so even after the worst is over, I can’t help feeling like a slab of meat prepped for the butcher.

“Relax…deep breaths,” Dr. Seal says, gently prodding at my abdomen as I stare at the square tiles on the ceiling. “Any pain here?”

“A little.” I clench my teeth to keep them from chattering. “But I’ve been hitting the caffeine pretty hard lately, so I’m sure that’s part of it.”

“Not great for endometriosis,” she says mildly, repeating what I heard from my OB back in Palo Alto before I moved. “But I’m sure you know that.”

I smile. “Yes, but I love coffee more than I hate pain.”

She laughs, motioning for me to sit up. “Understandable. But if the cramping gets too bad, let’s talk about what you might want to eliminate from your diet, okay?”

“Got it,” I say, smoothing my gown down over my knees.

“So is there anything else you wanted to discuss today?” Dr. Seal asks, her brown eyes warm. “I’m assuming you have birth control in place that works for you?”

“Um, yes. I do.” I clear my throat as I nod. Swearing off relationships until I’ve got everything at the winery and tasting room running smoothly is certainly effective birth control, but I know that’s not what she means.

“Great. But if you decide you want to explore other options, give us a call. It can take time to get an appointment with me on busy weeks, but Nancy, our nurse practitioner, is wonderful and can always talk you through your options.”

“Speaking of options,” I find myself saying before I realize that I’m going there.

I didn’t plan to discuss this today—I have enough on my plate without adding another major life change into the mix—but now that I’ve started I don’t want to stop.

“I’m wondering about…babies,” I say, pulse speeding simply from speaking the word aloud. “I’d like to have a child sooner rather than later, but my ex and I tried for nearly a year without any luck, and I know endometriosis can make conception more difficult. Do you think I should start trying soon? If I want to have a baby before thirty-six or thirty-seven?”

I have no idea how I’m going to start “trying” at this point, but if Dr. Seal says the time is ripe, I guess I can start checking out the local sperm banks.

The doctor’s brow furrows as she rolls her chair over to the computer screen, glancing at my chart. “You’re thirty-four?”

“Yes,” I confirm. “Thirty-five in a few months.”

She hums low in her throat. “Assuming there’s room in your life for a child now, I would encourage you and your partner to go ahead and start tracking your cycle and timing intercourse on your most fertile days. And if you don’t conceive within six months this time, then we can discuss more aggressive options. I can walk you through those myself, or refer you to a colleague of mine who specializes in pregnancy in women of advanced maternal age.”

I laugh, but her expression assures me she’s not kidding. “Um, advanced maternal age? I…I’m not there already, am I? I mean, I thought I had time. At least a little.”

“You absolutely have time,” she says, in a voice I can tell is meant to be reassuring, but isn’t. “But traditionally, women aged thirty-five or older are considered to be of advanced maternal age. Fertility decreases rapidly between the ages of thirty-one and thirty-seven, and then even more rapidly as you move toward forty. As long as you know you want a child, it makes sense to start as soon as possible. So I’ll give you a prescription for prenatal vitamins, instructions on how to track fertility, and hopefully we’ll be able to get you on the road to becoming a mom soon.”

Becoming a mom…

Oh my God. A mom…

Tears spring into my eyes, but they aren’t sad tears this time. They’re hopeful tears. Honest tears. Tears that assure me that yes, this is what I want, what I long for more than anything, what I need to make my life complete. I need that little boy or little girl I’ve been dreaming of for so long in my arms, in my heart, where I will keep him or her forever.

Swallowing past the lump in my throat, I nod, smiling through the mistiness blurring the edges of Dr. Seal’s face. “Yes, that sounds perfect.”

And it does.

But it’s also…complicated.

As I wander out the door and make my way toward where I parked my bike near the town square, I start asking the harder questions like—do I really want to have a stranger’s baby? Some guy who spent a few minutes jerking off to porn in a windowless room in exchange for whatever sperm banks are paying for deposits these days? Sure, I’ll be able to check out his genetic history, education, and I think they even show pictures sometimes, but I won’t be able to look into the man’s eyes in real time and see if he’s one of the good guys.

I’m a big proponent of the gut check. I don’t care how good you look on paper, if you trigger a “not safe” signal in my lizard brain, we’re not going to be friends, let alone create a life together. I’m not sure if creepiness is an inheritable trait, but I’m not willing to risk it, at least, not as long as I have other options.

But do I? And if so, what are they?

A few minutes later, I guide my bike into the winery’s drive and keep going, past the tasting room where Denver and Neil, my two ruthlessly charming hosts, are pouring wine for three couples who arrived in a stretch limousine.

Usually I would pop in to say hello and visit for a while, but I need to conserve my energy. Bart, my vineyard manager, told me this morning that the grape sugar levels are right where I want them to be. Which means we’ll be starting our harvest at two a.m. tonight to ensure the fruit doesn’t get warm on the way from the vine to the crush pad.

That also means an afternoon pleasure ride isn’t in my future. But that doesn’t mean I can’t find a place to enjoy the sights.

I roll onto the multi-use trail that runs through the heart of the Green Valley wine region. It’s truly a stunning gift to the people of this county, chock-full of rolling hills, vineyards, apple orchards, and adorable Wine Country cottages, with plenty of strategically placed benches for sitting and enjoying the breathtaking views.

Today, my favorite bench—the one dedicated “To Grandma Mona with All our Love,” with a vista of my own vines—is taken by two women in their mid-twenties, sharing a bottle of wine, a basket full of goodies, and a serious case of the giggles.

The sight makes me lonesome for my sister, who also happens to give tremendous advice in times of trial.

Once I’ve parked my bike and settled on my second-favorite bench a few yards away from the other women, I pluck my phone from my basket and pull up Carrie’s contact info. I’m trying to decide whether to text or call, when Giggler Number One says something so interesting, I can’t help but pause to eavesdrop.

“Seriously. The Hunter men are famous for it. Women stand too close to them, and they end up pregnant. It doesn’t even require penetration. A Hunter man can knock you up with a hug. Even a handshake is dangerous.”

Her friend laughs. “Stop it. You’re scaring me.”

“You should be scared,” Giggler One insists, doubling down. “This isn’t an urban legend. This is the real thing, backed up by a family tree with more branches than spokes on my bicycle. Hell, you might be pregnant already just from the intense eye contact you and Rafe had going on.”

Friend starts giggling again. “Oh my God, it was intense. He’s so incredibly hot.”

“So hot,” Giggler One agrees.

“So I don’t care if he’s got super sperm.” Friend swirls the straw-colored liquid in her glass with a jaunty wiggle of her shoulders. “My diaphragm and I are going in, girlfriend. It’s been too long since I’ve been with someone who looks like that in jeans.”

But Dylan looks even better, I silently add.

Dylan looks phenomenal in jeans, and he’s also a Hunter, one of these hypermasculine creatures rumored to have legendary fertility. And he’s not a creep, not even close. From everything I’ve heard around town, if you’re not bidding against him for a piece of property, he’s a nice guy. And even though I’m clearly not his favorite person, he’s never been unkind to me.

He just…doesn’t like me very much.

Right. He doesn’t like you, psycho, let alone LIKE you. Why on God’s green earth, would he even consider putting a bun in your oven?

“Because I have something he wants,” I murmur aloud, text and call forgotten.

I tap the edge of my cell against my lips, heart racing as a plan begins to form.