Dr. Peter Palma joins the medical team of the Paradise to treat passengers for minor ailments as the cruise ship sails across the Atlantic. But something foul is festering under the veneer of leisure. The brig fills with felons, the morgue with bodies, and the vacation becomes a nightmare.
Peter and his staff face a vile affliction that pits loved ones against each other and shatters the bonds of civil society.
With the ship hurtling towards an unprepared New York, only Peter can neutralize the threat, but he’s hallucinating and delirious.
And sometimes primal urges are impossible to resist.
“With tight pacing, visceral horror, and sharp psychological insight, The Regression Strain explores what happens when science, instinct, and morality collide in the vacuum of survival…claustrophobic, haunting, and razor-sharp”
~ K.C. Finn for Readers’ Favorite
“I am very impressed with Hwang’s first novel. He has an ability to draw in his reader within the first few pages. There were some unexpected twists and heartwarming moments. I look forward to reading more by this author.”
~ Amazon reader
“Hwang’s debut is fast-paced and propulsive, and I loved the medical mystery at the heart of the thriller. He’s great at crafting creepy scenes that will stay with you!”
~ Amazon reader
“I really enjoyed this novel. I was hooked from the beginning, wanting to know more about the mysterious illness and the troubled backstory of Peter, a doctor grappling with his past whilst trying to have a fresh start in life with a new job on a cruise ship. The author Kevin Hwang portrays Peter with such realism and empathy. Hwang’s keen eye for people’s inner monologue and perspective on their secret struggles must be informed by his years of work as an internist. Ultimately, Hwang’s story is a fast-paced thriller that reveals the darker side of human nature lurking in all of us. I had trouble putting this book down and can’t wait to read his next novel!”
~ Amazon reader
“This is an excellent thriller, with plenty of plot twists and turns that kept me guessing. It packed plenty of excitement and intrigue with excellent medical knowledge from the author. You don’t want to put this down until you’ve finished reading.”
~ Amazon reader
Chapter 1
The Regression Strain
As the cab rounded the corner behind the service buildings, the full bulk of the ship rose into view, a floating city gleaming white and blue against the gray Baltic sky. The Paradise would be Peter’s home and workplace for the next month.
His shoulders tightened. Had he forgotten to pack anything? It was too late now.
The taxi ejected him into the cool summer of Copenhagen—heaven compared to the stifling heat of Texas. He checked in at the terminal counter, cleared security, and joined the stream of chattering passengers traversing the covered gangway to board the vessel. Most of them spoke in English and a few in Spanish. Others conversed in German, French, or Scandinavian tongues. They seemed affluent and confident, not at all like his impoverished patients in Houston’s Fifth Ward. That guy in front—his Rolex probably cost more than Peter’s Outback.
Peter wheeled his suitcase through a colonnade of clapping crew members and across the threshold of the grand atrium. Its rich wood paneling and glittering chandeliers were as opulent as the brochures promised. He fused with the crush of passengers piling up in front of the diagrams posted near the elevators. Living quarters for the medical crew were on the lowest deck, conveniently adjacent to the clinic.
Amid the throng, a woman was fussing over a teenage boy in a wheelchair. She leaned in and whispered something in his ear, then tousled his thick mop of brown hair. With one hand cranked tight against his chest, he lolled his head back and rewarded her with a crooked smile. Her haggard face lit up. Now that was one tired mama.
“I like his shirt.” Peter pointed to the graphic of Thor wielding his massive hammer.
“You hear that, Calvin? He likes it.”
Calvin’s nose crinkled above the sparse stubble dotting his chin. She retrieved a ChapStick from her floral fanny pack and slathered Calvin’s lips first, then her own.
She offered the tube to Peter with a glistening smile. “Want some?”
He cringed. That was weird. “Uh, no thanks.”
“Want him?”
Peter’s eyes snapped up to hers. “Excuse me?”
“You can take him for a while.” She smiled and tipped her head. “He doesn’t eat much.”
“Ah…”
“Ha ha, it’s a joke.” She licked her moistened lips. “I’ve been on this boat too long. Cabin fever.” She gave him a little nod and wheeled the kid into the elevator.
The adjacent elevator dinged open, revealing a family that looked right at home, mom admiring the decor, two school kids horsing around. Sipping coffee in his striped polo, dad looked a bit like Peter’s microbiology professor—placid and plump.
Peter pulled his suitcase to the side with a smile. It was nice to see people relaxed and carefree. And if they needed medical attention—well, he could offer it. It would be a relief to simply treat patients. No rationing medications against their rent. No fighting through nettles of bureaucracy just to get a CT scan. He wasn’t built for that fight, and the last few rounds had left him bruised.
The younger child in the elevator darted out. Mom lunged and grabbed his collar, jostling dad into Peter. Coffee sloshed out of the man’s cup and down his jeans.
An animal snarl flashed over the man’s pale, doughy face. “Watch it, prick.”
“Sorry, I didn’t expect…”
The man leaned in, eyes glowing hot behind round bifocals.
Peter jerked back. “Whoa, are you okay?”
As the man cocked his fist back, Peter watched the sleeve of his polo shirt ride up his bicep, almost in slow motion. Peter quickly raised his open palms.
“Honey,” mom hissed. She tugged her little one back, and he huddled under her frail wings.
The man lowered his fist, the stench of coffee hot on his breath.
Peter nodded. “It was an accident. I’ll buy you another coffee. Or jeans.”
The heat in the man’s eyes dissipated and he blinked a few times, looking at Peter’s face yet his attention was directed elsewhere. “Ah, shoot.”
Sorry, mom mouthed and hustled the whole family away.
Peter stepped into the elevator among passengers who seemed oblivious to the encounter. His heart hammered in his chest, and his mouth soured with adrenaline. Microbiology professor? Scratch that—this guy was more like that assistant principal caught in a minivan with the high school girl. And here he’d nearly gotten into a fistfight on his first day.
But hey, he’d defused the situation. He was still supposed to be here. This was going to work out. He closed his eyes as the last passengers got off and the elevator continued to the bottom level.
The doors opened onto a hallway with plush burgundy carpet and polished handrails. Colorful abstract prints enlivened the walls. This was where everything could begin again, even at age thirty-two. He would be a healer on the high seas, applying his hard-earned expertise to help people on vacation.
But the aura disintegrated when he opened his cabin door. Inside was a single bed, a nightstand no larger than a magazine, and a built-in desk with a swivel chair. The sheets lay twisted in a lump at the foot of the bed, exposing a mattress with stains the color of dirty bathwater. A smudged TV hung crookedly from the ceiling, and a stale scent lingered in the air. The only feature that distinguished the cabin from a hospital on-call room was the round porthole window giving view to rusty shipping containers on the dock.
Well, he wasn’t on vacation, after all, even if everyone else was. Peter heaved his suitcase onto the lumpy mattress and began stowing his clothes. Luckily he’d packed light for this trial run. The tiny closet contained a white uniform, starched and waiting like a suit of armor, as well as an orange life vest and a safe the size of a cigar box.
The only real valuable he’d brought was his new 3M Littmann Cardiology IV, an upgrade from the battered stethoscope from residency. He fished around in the side compartment of the suitcase but came up empty. It should’ve been right there.
He checked every zippered pocket, then rummaged through his backpack. Nada. How could he have forgotten his freaking stethoscope, of all things? He’d followed his packing list. He loved lists, for heaven’s sake, loved checking off each item. Little good it had done. He drew a deep breath in then out, trying to clear his mind by counting to ten like the therapist said.
Ten seconds was a long time to think about nothing. Maybe he needed a higher dose of Lexapro. He’d been reluctant to accept his diagnosis, one he himself had given to so many patients, but the antidepressant seemed to help with his mood, concentration, and sleep.
The ambiance of the bathroom matched that of the bedroom, with black spots of mildew mottling the lower edge of the shower curtain. The sink offered little space for personal items.
He opened his bottle of Lexapro, shook a tablet into his palm, and swallowed it dry as he stared into the dingy mirror. Working aboard a cruise ship would be a huge change, and he needed to bring his best. He set the bottle on the narrow counter, but it clipped the edge, flipped out of his hand, and plopped into the toilet with an insulting splash.
His stomach clenched and he squeezed his eyes shut. Maybe, by some miracle, the bottle had landed upright with the tablets safe and dry inside, like a lifeboat. A tiny boat in a tiny toilet on a gargantuan ship.
He peered down. Nothing doing—the bottle floated on its side, surrounded by white tablets bobbing in the murky water like pearls of pasta in chicken broth. Why did the water have to look like that? Was it just reflecting the grimy inner surface of the toilet bowl?
Didn’t matter. His mental health was officially soaking in shit.
The half-life of Lexapro was around thirty hours, and he’d taken one yesterday back in Houston. He could just retrieve the tablets, wash them off, and dunk them in rubbing alcohol. Without more doses, the effects would diminish over the next few days. He could picture his exit interview: I’m sorry, Dr. Palma, you came ill-prepared.
One hand drifted to his pocket. At least he’d remembered to pack his favorite metallic pen. Even in the age of digital everything, a quality pen remained one of his favorite tools—that and old-fashioned index cards. His fingers closed around the pen, clicking the top: Ta-tick, ta-tack. Ta-tick, ta-tack.
Someone knocked on the door, but the bolt clicked open before he could reach it. The slight, olive-skinned man turned back to the hall almost as quickly as he’d come in. White shirt and charcoal vest—must be a steward.
“I’m sorry, I come back later,” he said with a duck of his bald head.
Peter waved him in. “It’s all right. I just got here.”
“Nobody clean your room yet?”
“I guess not.”
“You the doctor, no?”
“One of them.” He propped the door open for the man’s cart.
The steward glanced around the tiny room. “It will be my pleasure to serve you. I come later when you have gone out.”
Peter suspected the man’s cheerful acceptance hid the same bone-deep fatigue that had weighed down his own mother. She used to clean offices, back before Felipe joined the army, and she was always exhausted. Chemical fumes permeated her clothes and hair, and her knuckles cracked and bled until he bought her the non-latex gloves that her cheap-ass boss wouldn’t pay for.
Before Peter could return to the bathroom, somebody else came knocking: a petite woman in blue scrubs, probably late thirties. A tight ponytail held back her glossy chestnut hair. Her sharp cheekbones and jawline were all business.
“Luisa Calderone, nurse on staff.” The strength in her bony handshake matched the intensity of her hazel eyes. “They said this is your first gig.”
Yep, a fresh start, a sorely needed one. “Sorry. I’ll try to learn quick.”
“We can do a proper tour later, but let’s just walk and talk for now.” She nodded back at the hallway. “I can give you some time to get changed, but we have patients—so not too long, please.”
Right back into it, then. He was a kid on a roller coaster cresting the first big incline—the moment before the bottom fell out. He opened the closet and confronted his uniform. Sure, he’d paid for the ride, but that didn’t make it any less stomach-churning.
***
Excerpt from The Regression Strain by Kevin Hwang. Copyright 2025 by Kevin Hwang. Reproduced with permission from Kevin Hwang. All rights reserved.
Kevin O. Hwang, MD, is a professor of internal medicine at McGovern Medical School at UTHealth Houston where he sees patients and teaches residents. His academic work has appeared in leading medical journals. Nothing excites him more than chicken enchiladas, index cards, and appropriately sized packaging. The Regression Strain is his debut novel.
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