The body lay in the salt flat behind the feed store, and Greta Voss knew she had two hours before the wind erased it. She crouched in her white coat and pulled on pale gloves. The sheriff stood ten feet back with his hat in his hands. He wanted her to talk. She would not talk until she was sure. The dead man was face down. Around him, the dust held a story. Greta read it the way her father read weather. One set of prints came in slow. The killer had stood still beside the body long enough to leave two deep heel marks. Waiting. She had seen that same still print last month, on a case she still could not close. She brushed a gloved finger through the powder near the man's collar. Pale grit lifted onto the leather. Not the yellow dust of the flats. Something whiter, finer, almost chalk. She had bagged the same trace before. No prints on the body. No prints on the belt buckle. Only that dust. "Voss," the sheriff said. "Give me something." "Not yet." A black shepherd sat at the sheriff's heel, ears forward, eyes on her hands. The dog had tracked the scent from the road and stopped here. It would not go past the body. Greta noted that. The killer had left on foot in a direction the dog refused. She walked the perimeter twice. She measured the heel marks. She compared them in her notebook to the sketch from last month. Same depth. Same wait. Same pale dust on the victim's shirt. Same killer. She was certain of that much. She was certain of nothing else. One body could be an accident of method. Two bodies were a habit, and a habit had a shape. But she had only one crime scene on paper. The first killing, months back, had been logged as a ranch death. No samples kept. A bleached cattle skull had been propped on the fencepost above that body, and the deputy on shift had written it off as a prank. Greta had argued. She had lost. She stood and faced the sheriff. "It's the same man who did the ranch hand in spring." "You told me that was nothing." "I told you I wasn't sure. Now I am." He stared at her. "One print and some dust." "He waited beside both of them. He'll do it again." The sheriff looked at the dog, then at the horizon. "Bring what you have to the station tonight. If it's thin, I can't move on it." She drove into town with the sample jar on the seat beside her. The police station squared the corner ahead, lamps already lit. She had one scene on file and one in her notebook. She needed a third she would not get in time, or a way to make two speak like three before the wind came up again.

Greta drove back to the salt flat with the wind already rising. The sample jar rattled on the passenger seat. She had one hour, maybe less, before the heel marks softened and blew flat. The sheriff wanted concrete evidence by nightfall. Two prints in loose dust would not survive the drive to the station, let alone his desk. She parked behind the feed store and got out. The building's shutters banged against the siding. Grit hissed across the flats in low sheets. She pulled her coat tight and walked to the body's outline, now a shallow smear in the powder. The deep heel marks were still there, but the edges were crumbling as she watched. She knelt and tried her camera first. The light was flat and the marks disappeared in the frame. She tried a ruler and a sketch. The wind lifted a corner of her notebook and tore the page. She swore once, quietly, and pressed her gloved palm to the dust to shield it. The print under her hand kept dissolving anyway. She needed to lift the marks, not photograph them. She needed to cast them. She had no plaster in the truck. She had nothing in the truck that would hold a shape. She stood and looked at the feed store. The shutters were closed but the side door was not padlocked. She tried the handle. It gave. Inside, the walls were warm brown wood and the air smelled of grain. Sacks were stacked along the shelves. She scanned the labels. Cracked corn. Sweet feed. Mineral salt. On the bottom shelf sat a row of tins and one heavy paper bag stamped with a picture of a horse's hoof. Hoof patch. Quick-set. She read the back. Mix with water. Sets in four minutes. She took the bag and a plastic tub and a jug of water from the sink. She left a twenty on the counter under a bleached longhorn skull that hung above the register, its horns catching the lamp. She did not have time to find the owner. Outside, the wind had chewed one heel mark down to a shadow. The other still held. She mixed the patch in the tub, poured it slow into the good print, and set her body between the mark and the wind. She counted to two hundred and forty. When she lifted it, the cast came up whole. A clean heel, deep at the back, worn at the outside edge. She turned it in her hands. The sheriff could hold this. He could set it on his desk. She wrapped the cast in her coat and carried it to the truck. The second mark was gone by the time she looked back. One was enough. One she could put in his hand. Then she saw the pale dust smeared along the cast's underside, thicker than any she had bagged before. It had come from the ground under the print. The killer had stood in it.