When Li Junjie (played by William Chan) was a child, his family was happy and his parents were both top scientists. But when he was 12 years old, his parents died unexpectedly while being sent to Bacheng. No relatives were willing to adopt him, so he was sent to an orphanage in Chonghai, his hometown. In the orphanage, Li Junjie met Shi Yunhao (played by Guo Jiahao), and Li Junjie's active protection made the two of them best friends. After that, Li and Shi met Chen Gang (played by Guo Guangping), who was also a brother and a father, and entered Bacheng Moshi. In the Moshi training camp, the two met Zhou Zixuan (played by Nazha) at the same time, and both had a different feeling for her, but Zhou Zixuan had a special liking for Li Junjie. At this time, Shi Yunhao chose to withdraw and guard silently. Just when Li Junjie's life was gradually getting on track, his impulse during a mission caused Chen Gang to die unexpectedly. Under the heavy blow of this incident, Li Junjie chose to leave without saying goodbye and track down clues alone, catching the murderer Jialai (played by Chen Chuhan) to avenge Chen Gang. After leaving Moshi, Li Junjie followed Calais, but he was always one step behind. When he was at a loss, a mysterious email with the Moshi logo guided him back to Bacheng, where he had been away for a long time. After returning to Bacheng, Li Junjie, under the pressure of Moshi Director Mou Chuan (played by Simon Yam), fought side by side with Zhou Zixuan and Shi Yunhao again, and finally caught Calais while carrying out the task of escorting VX3. The three of them put aside their past grudges, Li Junjie and Zhou Zixuan regained their feelings and tacit understanding, and Shi Yunhao once again lost the opportunity to confess to Zhou Zixuan. I thought that catching Calais was the end of the matter, but Calais was rescued by prison. Later, a mysterious code appeared, the "Scorpion" organization surfaced, and there was another hidden story behind Chen Gang's murder. The three of them discovered that there was a bigger conspiracy waiting for them behind all this...