Main plot (highlights): China in 1920 was in a dark and stormy time. Shen Yan, a calm and reserved Communist Party member, sticks to his faith in the turbulent situation and secretly carries out revolutionary work. He moves among various forces, not only having to deal with the high-pressure suppression of warlords, but also resolving internal differences and suspicions. On this thorny road, he fought side by side with like-minded people and also encountered betrayal and sacrifice. The story uses a realistic style to show Shen Yan's struggle and perseverance in the torrent of history, depicts a real group of early communists in a complex political environment, highlights the collision between ideals and reality, and restores the difficulty and greatness of the revolutionary cause of that era.