I got the math wrong for seven months because I thought love was something you measured in hospital parking receipts and the number of clean pillowcases left in the linen closet at home. The gravel out by the St. Jude’s employee entrance crunches a certain way under the tires of the supply trucks, a heavy, dull sound that used to make my stomach tighten up every single morning before I even turned the ignition off.

I spent two hundred and twelve days believing that Eric was dying in room 314 because Dr. Vance had a neat, expensive signature and a way of looking over the top of his half-moon glasses that made you feel like you were holding a glass vase with cracked handles. When you spend enough time walking down a corridor that smells like floor wax and boiled cabbage, you start to forget what the outside air actually tastes like. You stop noticing the way the sun hits the top of the parking garage at four in the afternoon. You just become another shadow leaning against the wall, waiting for someone in white scrubs to come out and tell you whether you are allowed to cry yet or if you have to wait for the evening shift change.

The stranger didn’t look like a prophet or an angel or any of those things people talk about when they want to make a bad day sound like a movie.

She was wearing a trench coat that had seen too many autumns around the collar, and her hair was pulled back into a clip that was missing one of its plastic teeth. She sat down on the metal bench beside me while I was trying to scrape a dried piece of chewing gum off the toe of my loafer with a rusty paperclip. My fingers were shaking so hard I could barely hold the metal steady, mostly because Dr. Vance had just spent twenty minutes telling me that Eric’s white blood count had dropped another point and that we should probably start thinking about the local hospice registry. I had a brown paper bag from the cafeteria sitting between us with a lukewarm carton of milk and a sandwich that tasted like damp cardboard. She didn’t say hello or excuse me or ask if the seat was empty. She just reached out a hand that smelled faintly of peppermint oil and laid three fingers right across my wrist until my paperclip dropped onto the concrete with a tiny clink.

Set up a hidden camera in her room, she said, and then she paused just long enough for me to look up into eyes the color of a wet slate shingle. He is not dying.

I remember staring at her until my eyes watered from the wind coming off the highway behind the dumpsters. My throat felt like it was full of sand and old carpet lint. I tried to tell her that Dr. Vance had the charts right there in his binder, that we had the lab slips from three different labs in Dayton, that Eric could barely lift his head off the second pillow without groaning like a man who had lead sewn into his ribs. She didn’t blink once while I talked. She just reached into her deep coat pocket and pulled out a little black square no bigger than a matchbox, with a glass eye that caught the gray light coming off the overcast sky.

Trust me. Set up the camera. You deserve to know the truth before he cleans out the joint savings account to pay for his medical travel fund. Then she stood up without another word, her heels clicking against the sidewalk until she turned the corner toward the bus shelter by the laundry mat.

Eric had been sick for eight months, or at least that was the story we told the neighbors on Maple Street and the ladies down at the parish hall who kept dropping off casserole dishes with aluminum foil tops. It started with a cough that sounded like a dry leaf scraping across a basement floor, right around the time he started coming home from his regional sales meetings three hours later than usual with his hair smelling like expensive hotel soap instead of the diesel exhaust from the warehouse. I remember standing at the kitchen sink while the evening news droned on about some bridge repair down on Route 4, watching him scrub his hands at the basin until the skin between his knuckles turned that raw, angry red. He told me the regional office was restructuring, that the board wanted him to take on the entire Tri-State territory without an assistant, and I believed him because he looked tired in that quiet, noble way that men get when they are working themselves into the ground for a mortgage that never quite gets smaller.

The first real crack in the plaster came on a Tuesday in November when the pharmacy called about the refill on his pain patches and the girl on the line asked if Eric Sterling wanted the generic brand or the name-sort that was covered under the secondary policy we didn’t have. I stood there with the black plastic receiver pressed against my ear, looking out at the dead hydrangeas in the front bed, and told her there must be some mistake because Eric’s care was being handled through the major medical rider on his corporate benefits package. There was a long, dry click on the other end of the line, followed by the sound of someone shuffling papers before she told me that the corporate rider had been canceled back in August at the employee’s direct written request. My hand started to sweat against the plastic until my fingers slipped down the curve of the handle. When I asked Eric about it that night while he was propped up on the sofa with a plaid blanket over his legs, he didn’t look up from his tablet. He just let out a long, wheezing sigh that made his shoulders dip down toward his chest and told me the insurance company was incompetent and that his manager had promised to sort the paperwork out by Friday.

I bought the little black camera at a security shop off Route 72 behind the auto parts store, paying cash for it out of the grocery envelope I kept behind the flour tin in the pantry. The man behind the counter was half-asleep with a toothpick between his teeth, and he didn’t even ask me what I needed it for when I pointed to the shelf with the nanny lenses and the motion-activated domes. It took me twelve minutes to figure out how to sync the little lens to my phone using an old burner email address I set up in the car while the engine was still ticking. The hardest part wasn’t the technology. The hardest part was knowing that once I stuck that little magnetic base behind the plastic housing of the wall-mounted air vent in room 314, I wouldn’t be able to turn back into the woman who believed her husband’s stories about his white blood cell count.

Eric was scheduled for a bone marrow scan down on the fourth floor at two o’clock on Thursday, which meant I had exactly forty minutes before the orderlies brought him back with his wheels locked and his eyes half-closed under the influence of the light sedative Dr. Vance liked to use for nervous patients. The room smelled like bleach and old oranges when I slipped through the door with my purse held against my ribs like a shield. I didn’t turn on the overhead lights. I just reached up toward the metal grate of the vent, my fingers feeling the cold, greasy dust that collects in those places where nobody cleans unless the health inspector is due on Tuesday. The magnet caught with a small, flat snap that sounded louder than a pistol shot in the quiet room. I pulled my hand back, wiped my palm down the side of my wool skirt, and walked out into the corridor just as the elevator bell chimed down the hall.

Dr. Vance caught me near the nurses’ station while I was trying to make my breathing look normal, his white coat crisp and smelling of peppermint and antiseptic soap. He told me Eric was resting as well as could be expected given the advanced state of the tissue degradation in his lower spine, and I remember nodding along like a good church member listening to a sermon she had heard three times before. You are a strong woman, Martha, he said, laying his heavy hand on my shoulder for three slow seconds before he walked away toward the pharmacy window. I didn’t tell him that I hadn’t felt strong since the day I found the dry cleaning receipt for three women’s silk blouses tucked inside the pocket of Eric’s winter coat back when the leaves were still green on the maples out by the fence.

I sat in my sedan in the hospital parking lot with the heater running and my phone resting flat on the center console between the gearshift and the emergency brake. The screen was black for six minutes while the camera booted up its internal loop, the little green dot blinking in the corner like a mechanical heartbeat that didn’t belong to anything natural. Then the picture cleared up, small and grainy and tinted that strange, sickly green that night vision gives to a room lit only by the streetlights outside the window.

Eric wasn’t in the bed.

The white cotton sheets were thrown back toward the footboard, bunched up in a messy heap that looked like someone had kicked them away in a hurry. Eric was standing by the small bathroom door in his gray undershirt and his flannel pajama bottoms, his shoulders squared back and his head tilted down toward a black leather briefcase that was sitting open on top of the small rolling table where they usually left the meal trays. He wasn’t leaning on his aluminum walker. He wasn’t using the metal cane with the rubber tip that he had spent the last two weeks complaining was too heavy for his wrists. He was lifting a thick stack of blue-backed bank folders out of the bottom of the case with both hands, his arms steady and hard under the skin without a single tremor to show for his terminal diagnosis.

I leaned forward until my forehead touched the cold glass of the steering wheel, my breath fogging up the plastic circle in front of the horn. My phone buzzed once against the console with a push notification from the app telling me motion had been detected near the secondary lens.

Then his voice came through the speaker, tinny and sharp and carrying that clear, carrying tone he used when he was chewing out a supplier over the phone down at the warehouse.

Yeah, the wire transfer cleared out of the main account this morning, he said, his face turned sideways toward the window so I could see the sharp line of his jaw without the gray shadow of the sickroom beard he usually grew for Dr. Vance’s benefit. The old woman at the house hasn’t suspected a thing. She thinks I’m too weak to lift a gallon of milk. Once the final property settlement goes through on Monday, I’ll be down in Sarasota before she even realizes the utility bills are still in her name.

I didn’t scream. I didn’t drop the phone. I just sat there in the dark car while the engine fan hummed its steady, high-pitched note, watching my husband pick up an electric razor from the counter and toss it into a canvas duffel bag like a man getting ready for a Tuesday morning business trip.

The second floor was quiet when I walked back through the swinging double doors at three-fifteen, my shoes making no sound at all on the rubber-backed runner the hospital laid down to keep the noise down for the dying people. The nurses were all clustered around the desk at the end of the hall, sharing a box of maple doughnuts someone’s daughter had brought in from the bakery out on Route 4. Nobody looked up when I passed room 314. Nobody asked me why I had my purse clutched against my ribs with both hands or why my face felt as stiff and cold as a piece of meat left out on the porch in January.

Eric was back in bed when I pushed the door open, his eyes closed and his breathing heavy and rattling in that theatrical way he had perfected over the winter months. The IV bag was hanging from its metal hook with the clear liquid dripping down through the little plastic chamber at two drops every three seconds, exactly where the nurse had left it during her rounds. The gray blanket was pulled up to his chin, and he had one thin, pale hand resting on top of the cotton sheet with his fingers curled slightly toward his palm to look weak and helpless.

I didn’t turn on the overhead light. I just walked over to the side of the bed and pulled the folding chair out from the corner, the metal legs scraping against the floor with a loud, abrasive screech that made Eric’s eyelids flutter open instantly.

Martha, he murmured, his voice dropping down into that dry, raspy register he used whenever he wanted me to fetch him a glass of ice water from the bathroom. You’re back early. Did Vance say something about the scan results?

I reached into my purse, my fingers finding the cold plastic of the phone and the heavy stack of papers I had printed out from our joint online banking portal while I was sitting in the car downstairs. I didn’t take my eyes off his face while I laid the papers down on the edge of the mattress, right where his pale hand was resting under the blanket.

You missed a spot on your shoulder when you were packing the canvas bag, Eric, I said, and my voice sounded like it belonged to someone else standing across the room, thin and flat and entirely empty of anything that used to live there.

He didn’t move for three seconds. He just lay there with his eyes fixed on the ceiling tile above the IV pole, his chest rising and falling with that steady, athletic rhythm I had watched on the small green screen five minutes before. Then he shifted his chin down toward the papers, his lips tightening into a thin white line that had nothing to do with terminal cancer and everything to do with a man who had left his ledgers unlocked on the dining room table.

Where did you get those? he asked, and the rasp was completely gone from his voice now, replaced by that cool, hard tone he used when he was firing a warehouse manager for losing a shipment of copper wire.

I got them from the room next door, I told him, reaching up to my collar to unpin the little gold brooch my mother had given me on our wedding day twenty-two years ago. And while you’re at it, you can tell Dr. Vance that his signature on your discharge papers looks a lot better when he isn’t being paid thirty thousand dollars to help you fake a terminal liver disease so you can run off to Florida with a girl who doesn’t know how to boil water.

He tried to sit up then, his elbows digging into the mattress as the mask of the dying man slipped off his face and left behind the angry, red-eyed stranger I had spent half my life trying to turn into a husband. He reached out a hand to grab my wrist, his fingers closing around my sleeve with a strength that could have crushed a walnut, but I didn’t pull away. I just looked down at his hand until his grip slackened and his fingers fell back against the sheet like a pair of dead fish.

You can’t prove any of this, he said, his voice dropping down to a hiss that sounded like steam escaping from a radiator valve. The accounts are in my corporate trust. The house is under the commercial holding company. You’ll be lucky if you get enough out of the estate sale to pay the back taxes on the truck.

I didn’t yell at him. I didn’t throw the plastic pitcher of ice water at his head the way I wanted to when I first saw him standing by that mirror. I just stood up from the folding chair, smoothed down the front of my wool skirt with both palms, and looked at the man who had slept six inches away from me through four different winters without ever once wondering what I was thinking when the house went dark.

The bank already froze the trust at three-forty, Eric, I said, turning toward the door with my purse tucked securely under my arm. And the woman in the trench coat down in the lobby? She said to tell you hello from her brother down in Cincinnati. The one you left with thirty thousand dollars of inventory and a fake divorce decree back in ninety-eight.

He didn’t answer me. He just lay there against the white pillows with his mouth half-open, staring at the empty doorway where the little black camera was still blinking its quiet green light from behind the wall-mounted air vent.

The afternoon sun was hitting the top of the parking garage when I walked out through the front doors of St. Jude’s into the cold November air, the wind tasting of wet asphalt and dead leaves from the park down the street. I didn’t look back at the three-story brick building with its rows of narrow windows and its neat white signs pointing toward the emergency entrance. I reached into my coat pocket, pulled out Eric’s contact card from the screen of my phone, and hit delete while I stood by the curb waiting for the traffic light to turn. The screen went dark, reflecting my own face against the glass for half a second before the display locked itself and went black. I slipped the phone into my pocket, zipped the heavy brass zipper all the way to the top, and started walking toward the bus stop by the laundry mat without looking down once at the ground beneath my feet.