Prologue

She threw the phone across the room and watched it bounce. She knew she should check the screen for damage but didn’t bother to get up from the couch. She was just so tired lately. She barely had the energy to get through the workday. She certainly didn’t have the energy for the conversation she was about to be forced into. If he actually showed up. He never had been great with follow-through.

She looked around her living room and considered what she’d have to change. The coffee table was glass-topped marble, all sharp corners and hard edges. The television stand could tip over. The afghan her mother had knitted for her was probably a choking hazard. Everything in her life was about to change, but the truth was she liked her life as it was. She liked being in charge of her time. She liked kickball and late nights with friends and the routine she’d built for herself.

The doorbell rang, and she reluctantly went to the front door. She glanced out the window, and there he was, smiling behind a bouquet of daisies. That smile that still made her feel like the prettiest girl in the world, though she was on the wrong side of thirty. She hadn’t been able to believe that someone as handsome and worldly as he would be interested in a nobody like her. He’d brought daisies to their first date, too, and by the time they left the restaurant, the flowers were too wilted to save. So he threw them away and went into the grocery store next door, came out with a fresh batch, smiling that smile, and it had been all over for her from there. She hadn’t even told her mom, knowing that she would only find reasons to criticize. He was too encumbered, too unsettled, too…whatever. All the things she liked best about him, her mother would hate.

Even now, despite the arguments they’d had over the last week, the back-and-forth and round-and-round that never seemed to lead anywhere, she felt a brief surge of pleasure and relief when she saw him. If anyone could help her find a path through the darkness that was closing in on her, it was him.

He handed her the flowers and bent down to take his boots off. The hunting knife he wore strapped to his ankle glinted in the overhead light. “You look terrible, Pooh-bear.”

She deflated. She knew she didn’t look her best lately, what with one thing and another. She was bloated and couldn’t bear the idea of the gym. But still…what a thing to say. When they’d first started seeing each other, he constantly praised her looks, her intelligence, even her clothes. As the months passed, though, the compliments had faded into memory. She couldn’t remember the last time she’d received one of those precious gifts.

“I didn’t think I’d see you tonight.”

“Yeah, well, I didn’t think you’d keep me out.” She could smell the alcohol on his breath. She shouldn’t have let him in. She should have made it clearer over the phone that he wasn’t welcome in her house. Not anymore. Not after the terrible things he’d said.

She took the flowers into the kitchen and busied herself finding a vase, trimming the stems, arranging them in ice water. Out of the corner of her eye, she saw him grab a beer out of her fridge without asking. Of course, that’s why she had them, right? She’d paid attention that first night and kept her fridge stocked since.

“Is that a good idea?” she asked, trying to keep the judgment out of her voice. Whatever was coming, she knew she’d be better off if he was sober. Not that he’d been violent. Well, not very, at any rate. It’s not like he hit her all the time or anything. He’d never broken a bone, never even bruised her face. Sometimes he just got carried away—and he certainly wasn’t the only one. She’d known lots of men who were the same way. All things considered, he wasn’t that bad. But she knew the conversation they were about to have was going to be emotional. Contentious, even. Sobriety seemed like a good starting place.

“Why not?” he asked and popped the cap off on the edge of the counter. He drank down half the bottle in one swallow, his Adam’s apple bobbing up and down. She wondered how many he’d already had and wished that just once a DUI patrol would have pulled him over.

“I don’t know what you think coming here is going to change,” she said. She looked down at her pajamas. Black. Oversized. She crossed her arms over her chest to make herself look even less inviting.

He dropped onto a stool at the bar and set his bottle on the counter. “I just think we should talk about it. Face-to-face. I think we should talk like civilized people, where you listen to my opinion, for once, and then we make a decision together, instead of you going off on your own and doing whatever the hell you want.”

She sighed. “You’ve made your opinion clear. I’ve listened to it. But this is my choice, not ours.”

He studied the bottle in front of him, empty now. She looked at it, too, trying to figure out what was so interesting about it. Her head was killing her—the afternoon’s tears coming back to bite her.

“That’s the thing of it,” he said. “I don’t think you really have listened to my opinion. If you had, you’d see I’m right. You’re just being an obstinate little bitch.”

Suddenly, the bottle shattered. Her first instinct was to grab a broom and warn him not to get up—he’d cut his feet. But then she saw that he was gripping the neck of the bottle and pointing the broken edge at her.

When the screaming started, she wasn’t sure at first if the noise was coming from his throat or her own.

Chapter One

Mackenzie Wilson yawned. The heat made her so sleepy. She pulled her sun hat lower over her eyes and contemplated the afternoon stretching before her. It couldn’t be earlier than four, probably, so another two hours before they could reasonably head back to the room to shower and get ready for dinner. Their seating was at seven. She scratched her arm, skin dry from the salt water. Two hours would be enough time for four more piña coladas in their tiny plastic cups. Maybe more, if the waiter came by regularly, and he had so far. She had picked the resort, and the reviews of the service—especially the beach service—had been one of its big selling points.

Mack had never been a fan of “the beach.” Between Ohio, New Hampshire, and Arizona, she’d never lived near an ocean, and she’d grown up afraid of the water. But when Beth Shankar, Mack’s new—well, girlfriend was too strong of a word, but friend wasn’t nearly strong enough—had found a flight deal to Cancun, Mack had for once agreed.

Mack had set up her out-of-office response, alerting those attempting to contact her at the Tucson District Attorney’s Office that she was out of phone and email reach until Monday, and she had mostly resisted the urge to check, had just left her phone in the beach bag she and Beth shared. The piña coladas helped, as did Beth’s delight at the chance to frolic in the gentle surf. The most helpful thing, though, was definitely the way Beth’s dark skin looked in her bright-red bikini.

They hadn’t been seeing each other long. After they’d met during the final days of an investigation into a serial killer the previous year and Beth had given Mack her number, Mack had resisted the urge to call for six weeks. It was Sergeant Dave Barton who finally convinced her.

“You only live once,” he said over dinner one night. “Call the pretty girl. Take a chance, Mack.”

Mack didn’t know if it was the wine that made her vulnerable or the fact that Dave was talking to her like he would talk to a teenage daughter. Either way, she’d called the very pretty Beth the next morning. Hadn’t even agonized about whether texting was the safer first move. Just picked up the phone and dialed, like she’d been doing it all her life. She still panicked when Beth answered, but she’d recovered and managed to ask her out to dinner.

Since then, six months had passed. They saw each other once or twice a week, usually, depending on their schedules. Mack was surprised at how easy it all was—Beth seemed to genuinely enjoy their time together but had never pushed for more. Sometimes, Mack wondered if Beth was seeing other people. She wouldn’t always pick up her phone, not that Mack called her often, but sometimes it took a day or more to hear back from a text. When Beth did get back to her, however, she always seemed happy to talk, and they always had a good time together. Besides, Mack reminded herself, Beth had been the one to suggest the Cancun trip.

She finished her drink, which didn’t have quite enough rum in it. Two more hours on the beach. She redid the math in her head. Maybe she could convince Beth to leave the water early, which would give them more time in the room before dinner. Heck, if they left the beach now, Mack was sure they could come up with other things to do for the entire rest of the weekend.

Drops of cool water falling on her bare stomach shook Mack out of her reverie. Beth was standing over her, fresh out of the Caribbean, laughing.

“Were you napping?”

Mack put her hand on Beth’s thigh. “Maybe dozing a little,” she admitted. “Your skin is so cold.”

Beth shook her head, intentionally spraying Mack even more. “You’re flushed,” she said. “You’ve been up here on the sand too long. If you were in the water, you’d find it delightful.”

She handed Mack a bottle of sunscreen, reached into their shared beach bag with one hand, and signaled to the waiter with the other. “Two more of these,” she called out, holding up Mack’s cup. She fished Mack’s phone out of the beach bag and glanced at the screen. “You’re blowing up in here.”

Mack grudgingly looked at her notifications. Her mother, asking if there was any risk of hurricanes in Cancun. Her dentist, reminding her of her annual cleaning the following week. Jess Lafayette, her best friend and colleague, setting up lunch for Monday. Then seven texts all from Dave Barton. Mack sighed and tossed her phone back in the bag without reading Dave’s messages. She’d respond when she got home, and until then she wasn’t interested in anything he might have to say about the cartel wars raging outside the resort zone.

“Remember the cop who was with me when we met?” she asked.

“Mmm,” Beth hummed. “Sorta. Bald, kind of short?”

“Yeah,” Mack said. “Really good guy. Dedicated detective, always brings me solid cases, went out on a limb for me in that situation last year.” She hated admitting that she had been the lead suspect in a series of murders that had actually been committed by Jess’ fiancé, but Dave’s role in that investigation had cemented their friendship. Mack had even started having dinner with Dave and his wife, Meredith, once a month. “Anyway, he’s been on my ass about this trip ever since I told him we were coming to Mexico.”

“Why?”

The waiter handed them their drinks, and they clicked cups before each taking a long swallow.

Mack flinched. “Brain freeze.” She waited for the pain to pass. “He thinks it’s super dangerous here. With the cartels and stuff. No matter how much I tell him that Cancun is safe, he doesn’t believe me.”

“He’s a cop,” Beth said. “Wouldn’t he know more about that stuff than you? The violence, I mean?”

Mack shook her head. “He does sex crimes and domestic violence. Not drug cases. I have three drug rips gone wrong on my caseload right now, and I texted the case agents when you suggested coming down here. They all promised me it was safe—one of them is bringing his wife and kids next month.”

“What’s a drug rip?”

Mack was surprised. Normally, Beth avoided talking about Mack’s work, and Mack was used to biting her tongue. Beth’s life had been blessedly free from the terrible things that one person can do to another—except, of course, for the time she’d found a corpse in a plastic tub at a trailhead—and she liked keeping it that way. Mack had gotten used to not talking about crime outside the office and was pleased by how natural the change was becoming.

“It’s when people meet up for a drug deal, but one really intends to rob the other.” Mack paused to make sure she chose the least violent way to describe a crime she had seen far too much of already. “Someone often ends up dead—either the buyer or the seller, or sometimes even a third party who isn’t a part of it.”

Beth shuddered and finished her drink. “I’m sorry I asked.”

Mack felt a momentary sting of rejection. She and her ex-girlfriend, Dr. Anna Lapin, might have talked too much about work, but at least Anna had understood where she was coming from. “Yeah. They can be…grim, I guess.”

Beth held out her hand for Mack. “Let’s go in the water,” she said. “At least sharks only kill you when they’re hungry.”

Mack stood, stretching. She remembered a documentary she had recently watched late one night while waiting for a verdict, which claimed sharks had been observed killing for sport, and she considered bringing that up but thought better of it. “Actually,” she said, fighting back her fear, “that sounds great.”