A medical helicopter roared through the sky and carried the emergency team to the scene just to save lives in prime time.This is a team racing against death, with the mission of moving the hospital into the sky and sending it to dangerous places. One day, four young doctors were sent to this vanguard medical team to join the brand new air emergency system.They embarked on the journey with their ideals and ambitions, but soon discovered that reality was far more cruel than they imagined.During the repeated emergency rescues, they face blood and death, and struggle on the verge of life and death; under high-intensity work, they have to re-examine their original aspirations and pursuits. They witness the fragility of life and witness miracles; they grow in pain and build deep friendships in each other's support.This journey is not only a tempering of medical skills, but also a baptism of the soul - they gradually understand that the so-called doctor is not only a cure of diseases, but also a person who ignites hope in despair. This is a story about youth, faith and growth, and it is also a hymn dedicated to the guardians of life.