Fengfeng threw the last cardboard box into the empty living room and stretched. The new apartment is located in the center of the neon-lit Cyber City. Outside the floor-to-ceiling windows, flying cars shuttle between skyscrapers like fireflies. He should have been excited to get the apartment, after all, as the hottest kickboxer in the league, he deserves the best. But he was distracted at the moment, his attention completely attracted by the weird things left by the former tenant.
The walls were covered with strange symbols, like some kind of encrypted messages. There were some old paper photos scattered on the desk. On the yellowed paper, a group of young people smiled brightly at the camera. One of the familiar faces made Feng Feng's heart shrink suddenly - that was Lu Yuan, his friend who had been missing for many years.
A folded piece of letter paper slipped from the album, with scrawled words on it: "Fengfeng, if you see this letter, it means that I have..." The end of the letter was torn off.
A chill climbed up the spine of the peak. Lu Yuan, a genius programmer, suddenly disappeared from the world ten years ago. Officially, he died accidentally, but Fengfeng always felt that something was fishy.
He began to carefully examine every corner of the room. In the desk drawer, he found an old-fashioned USB flash drive and a piece of paper filled with complex formulas.
"What the hell is this?" Fengfeng muttered to himself.
