3 ideas
Amanda names the 'rescue distance' as the invisible, elastic thread that measures how far her daughter Nina can stray before Amanda could no longer reach her in time. She constantly recalibrates it against visible dangers such as a pool or a road. The concept shows how parental vigilance rests on the assumption that threats are locatable and outrunnable, so the thread is useless against a danger that is everywhere at once.
Vacationing in a rural Argentine farm town, Amanda and her daughter Nina are exposed to poison after sitting in dew-wet grass near unloaded barrels, and Amanda lies dying in a clinic. Years earlier, the local mother Carla had a healer move part of her poisoned son David's soul into another body to save him, and afterward she no longer recognized him as her own. Nina is also taken to the healer and survives the intervention, though what she becomes is left unsettling.
The novella is built as a dialogue in which David repeatedly pushes the fevered Amanda away from details he calls irrelevant and toward 'the important thing' as she reconstructs the days leading to her poisoning. The conversation moves past the exposure scene into Nina's fate, and what the important thing ultimately is remains unresolved.