Dr Królikowski's orthodontic office looked ordinary only from the outside. It was the newest in town, and the seat in the waiting room smelled of mint and citrus. Laura and Bartek turned up here once a month to check their braces. But today something was different. For the first time, Dr Królikowski was unexpectedly late. The receptionist was nervously moving pens around, as if she was trying to hide something. A soft buzzing could be heard in the background, which shouldn't be coming from behind the closed door of the treatment room. When Bartek asked the grey-eyed boy who was also waiting for his appointment about it, he merely shrugged his shoulders, but Laura noticed that his eyes expressed concern. There was a new board hanging on the wall - a picture of a strange-looking microscope and the caption: "Meet the new technology for cleaning teeth!". Bartek looked at the picture and muttered: "I wonder why anyone would need a laser for cleaning braces?". The door to the surgery swung open quietly, although no one opened it. Laura smelled a strong odour of menthol, as if someone had poured litres of mouthwash in here. The receptionist suddenly stood up, her face betraying a slight fear. "Mr and Mrs Królikowski are just asking Laura to come inside for a moment," she announced unexpectedly. Bartek held out his hand to stop his friend: "Maybe don't go alone...", he whispered. Laura, curious and a little frightened, followed the receptionist through the narrow corridor. She noticed traces of toothpaste on the floor - they stretched all the way to the door of the orthodontist's office, through which there was now a clear light and the sound of toothbrushes rustling. As she crossed the threshold, she noticed something she had never seen before: in the centre of the office, above the chair, levitated a strange, pulsating ball of light. Something was evidently moving inside it, and the smell of peppermint toothpaste was all around her.... At that moment, she heard a loud crash, and the door slammed loudly behind her. She felt she was witnessing something she should never have seen....