Stella had always dreamed of travelling to space. When she got to the Astronaut Summer Camp, she couldn't believe her luck. Especially since her best friend Olek was going with her, who knew all the planets by heart and could make even the most fussy robot laugh. The camp was located on the huge Orbitron Station, suspended high above the Earth. Through the windows, they could see the blue orb of the planet, the rolling clouds and the rockets that occasionally flashed against the stars. The station had everything they loved: laboratories, flight simulators, long corridors and even its own garden with a mysterious purple plant that glowed in the dark. On the first day, after being introduced to the rest of the crew and undergoing training, Stella and Olek were given permission to explore the station on their own. They decided to explore the most forgotten part of the Orbitron - the old engineering section, where hardly anyone looked anymore. The corridors in this section were darker and the air smelled of dust and.... something else that neither of them could describe. Walking cautiously, they heard a quiet electronic beeping. They stopped at a door with a sign: "Signals Laboratory - Admission for staff only". - Do you hear that? - whispered Stella. - 'I think it's some kind of signal,' replied Olek, pulling out a pocket detector. The door was slightly ajar. A flickering blue light was coming through the crack. Olek looked at Stella and she shrugged her shoulders - they were both equally curious. Slipping inside, they saw old screens, covered in a layer of dust. One of them flashed a message in an unknown language, and next to it, on the desk, lay a strange, pulsating crystal. Suddenly, Olek's detector began to go crazy. The sounds it was making were unlike any known signal. Stella was about to touch the crystal when suddenly all the lights in the laboratory went out and dozens of small green lights flashed in the darkness....