The buildings on Nowy Swiat glistened in the setting sun. People lined the streets - some running nervously, others sipping lemonade, laughing under umbrellas. Maciek walked at a brisk pace, every now and then swiping his finger across the screen of his old smartphone. Seemingly an ordinary boy in a navy blue sweatshirt, but for the past few weeks he had felt that something was wrong. Conversations he had previously heard in the café began to acquire a new meaning - he could predict what someone was going to say before they opened their mouth. Sometimes it seemed to him that there was a code pulsing through the air - invisible threads that he could spot if he concentrated hard. In the evening he met Ola and Leon in the park by the Powiśle Power Station. They sat on a wall, listening to Led Zeppelin from Lea's phone. "Do you ever feel like reality... is starting to break down?" - asked Leon, outlining strange figures in the air with his hand. Ola shrugged her shoulders, but her gaze wandered somewhere beyond the edge of the sky for a long time. "It's as if someone is rewriting the world, and we just sometimes catch these lines of code," Maciek said, although he himself didn't quite understand how he knew the words. Leon laughed, but only for a second. "Maybe we're a glitch in the system?" - he joked. That evening they heard on the news about the disappearance of a computer science student from outside the University Library. The police had no leads. Maciek couldn't sleep. During the night, he entered a forum where people had been exchanging strange observations for days: shifting images on the street, unknown people appearing, repeating numbers on his watch. At three o'clock in the morning he closed the laptop and decided - tomorrow he would look for answers on his own. In the morning, the three of them stood outside the BUW considering where to start. Maciek looked deep into the glass door. He saw more than a reflection - rows of numbers that moved on the walls. He closed his eyes. In his head he heard a voice: "You can only change the code if you are vigilant." He almost jumped up. Ola grabbed his arm. "I see something ... strange," she said slowly, and her eyes shone with a pale green light. At that moment, a tram drove past - but stopped right next to them, even though the stop was a few dozen metres away. A boy in a black jacket with a strange sign on his hand got off. He looked straight at Maciek and then at his friends. "You know too much," he said quietly, moving towards them. Maciek's heart sped up, and lines of code flashed under his eyelids, ready to outwit them....