Deep in the depths of K University's School of Engineering, there is a little-known mysterious research group.Takaaki Jiangnan, who was once a member of this group, recently received a letter from Nakamura Seiji.The contents of the letter are confusing and seem to be inextricably linked to his past research.At this time, Miss Lab members from the same school were conducting training at the Kakushima Aojia Annex and Jukkakukan, which also provided Jiangnan with an opportunity to investigate.

Jiangnan decided to first visit Nakamura Seiji's younger brother, Nakamura Kojiro.He hopes to get more clues about his brother and the letter from Benijiro.At Benjiro's home, Jiangnan unexpectedly met a young man named Shimada Kiyoshi.Shimada Kiyoshi is a young man who is passionate about solving puzzles. His appearance surprised and excited Jiangnan.

The two had a great conversation and soon decided to cooperate to uncover the secret behind the letter.They began to carefully analyze every word in the letter, looking for possible clues and hints.At the same time, they did not forget to ask the members of Miss Lab about Nakamura Seiji, hoping to find more clues.

As the investigation deepened, Jiangnan and Shimada Jie gradually discovered that the letter seemed to be somehow related to their past research projects.Some of the anomalies and unsolved mysteries they discovered during their research seem to be inextricably related to Nakamura Seiji.They began to wonder whether Nakamura Seiji was also involved in their research, or knew some secrets that they didn't know?

In the process, Jiangnan and Shimada Kiyoshi not only solved mysteries one after another, but also established a deep friendship.They face difficulties together, share joy together, and work hard to uncover the truth together.In the end, with the joint efforts of the two, they successfully uncovered the truth behind the letter and found the answer they had been looking for.