Isla woke up to the smell of warm earth and lemons. She was staying at her great-aunt Imogen’s tiny house on a hillside, where the windows had no glass, only wooden shutters, and a fat orange cat called Rumi slept across the doorstep every afternoon.

Behind the house grew the olive trees. They were older than anyone Isla knew, with trunks all twisted and silvery, and their leaves turned over in the breeze so they flashed pale green, then dark, then pale again. Imogen said some of these trees had been giving olives since before her own grandmother was born.

“This week we pick the early ones,” Imogen said, handing Isla a small basket. “Just enough for a jar. The big harvest comes in autumn, but these few are special. They go to whoever has helped the most.”

Isla loved that idea. She picked carefully all morning, only the small green olives that came away with a gentle twist. Rumi followed her between the trees, batting at the ones that dropped, then losing interest and flopping into the shade.

By lunchtime the basket was nearly full. Isla counted them, because counting was the sort of thing she liked to do. Forty-one olives.

Then something strange happened. After her nap, she counted again. Forty. After she helped wash the cups, she counted once more. Thirty-eight.

“Imogen,” Isla said slowly, “my olives are disappearing.”

Imogen raised an eyebrow and smiled. “Are they now? Then you’d best be a detective.”

So Isla sat very still by the basket in the warm afternoon, with Rumi purring beside her, and she watched. The cicadas buzzed. The shutters creaked. Nothing happened for a long while. She was nearly drowsy when she saw it.

A little bird, sandy brown with a bright eye, hopped along the wall. It landed on the basket’s edge, picked up one green olive in its beak, and flew off across the terrace toward the old stone wall at the bottom of the garden.

Isla followed quietly. Rumi padded behind her, far too lazy to chase anything. At the wall, tucked into a gap between two warm stones, she found a small untidy nest. And there, lined up in a neat little row, were her missing olives. Three, four, five of them, arranged carefully beside a button, a bit of blue string and a chip of broken pottery.

“You’re not eating them at all,” Isla whispered. “You’re collecting them.”

The little bird landed nearby and watched her, not frightened, just curious. Isla understood then. The bird liked round shiny things, and her green olives were the roundest, shiniest things on the whole hillside.

She didn’t take them back. Instead she went to the kitchen and found a single olive, plump and perfect, and she carried it down and set it gently by the nest, a gift for a fellow collector.

When she told Imogen, her great-aunt laughed until her shoulders shook. “That little thief has been doing this for years. I always wondered where the olives went.” She looked at Isla with something proud in her eyes. “And you’re the first to catch her at it.”

That evening they ate supper on the terrace as the sky turned the colour of peaches. Imogen brought out a small jar, the very first olives of the season, and set it in front of Isla.

“To whoever helped the most,” she said. “And to whoever solved the mystery.”

Isla felt full and warm and pleased with the whole quiet day. The hillside went soft and grey, the cicadas slowed, and somewhere below the wall the little bird tucked her treasures away for the night.

Rumi climbed onto Isla’s lap, heavy and rumbling. The olive trees turned their leaves over one last time in the cooling air. Isla rested her head back, listening to the gentle creak of them, and her eyes grew heavier, and heavier, until the warm dark folded gently over the hill and she was asleep.