Oxygen. An Undesirable Element

Four hundred years after the catastrophe due to the lack of air on Earth, the corporation «Synthesis» took control of access to oxygen, and all people began to divide by status.
 
Zoe, a loner without relatives and friends with a lifetime... second status, works in an abandoned Archive of relics. When a renowned professor-ecologist is murdered in the building, she becomes the only suspect.
 
August — a member of the «Synthesis» Council with a ninth status — intends to find out what exactly the professor was looking for in the Archive on the day of his death. For the investigation, he teams up with Zoe, who must solve the crime to prove her innocence.
 
Among thousands of relics, they discover not only the secrets of the past but also a terrifying secret of «Synthesis» that threatens thousands of lives...
 
An interactive sci-fi detective in the spirit of cult YA dystopias «The Hunger Games», «The Maze Runner», and «Divergent». Solve the author's ciphers to find the criminal and uncover the secret of «Synthesis».