Lena enjoyed the silence in the cockpit of the tug Ladybird. Saturn's rings glittered like spilled sugar. Uncle Marek steered gently, dodging lumps of ice. Today they were to catch old buoys and wires. Suddenly something tapped on the side: tick, tick, tick. It didn't sound like the usual thump of ice. The rhythm repeated itself, even as a school tune. "Do you hear that, Uncle?" - Lena asked. Marek squinted and reached for the bow camera. A small metallic point blinked in the image, too smooth for a rock. They flew up cautiously, switching on the microdisks. The object was stuck in the snow dust, like a forgotten beacon. It looked like a lunch tin, but had a pitch antenna. On the side someone had scratched: "Do not open in a vacuum". "Who lost it at Saturn?" - muttered Marek. "Maybe someone who wants it back." - replied Lena. They grabbed the capsule with a grabber and slid it into the airlock. Inside the ship, the lights dimmed as if something had taken a sip of electricity. A quiet buzzing sound came from the capsule, and then the rhythm again: tick, tick, tick. "Pressure balanced" - reported the computer. "Shall we open?" - Marek asked, handing Lena the gloves. The girl's heart was pounding, but curiosity was greater. She unscrewed the first clamp, then the second, the third. The radio beeped and the letters flashed on the screen: LENA, LENA, LENA. "Jokes?" - breathed out her uncle. On the outside camera, something moved across the sand of the ring. The shadow had the shape of someone's hand. The capsule twitched, as if responding to the touch. "Now!" - whispered Lena and lifted the lid, and at the same moment the alarm howled louder than ever.