On Christmas Eve, the weather was unusually hot, and the whole city was inexplicably strange. The high-load power station was in danger, and the fire department was on guard. The firefighters were full of their own worries, making this "hard battle" full of emotional entanglements. Ho Wing-sum (Nicholas Tse), You Bang-chao (Shawn Yue), and Ye Zhihui (Andy On), the three have been brothers for ten years, but now they have their own concerns: Ho Wing-sum, who was highly appreciated, was transferred from the fire department, and he was unwilling; Ye Zhihui played with interpersonal relationships and was promoted the fastest; You Bang-chao was free and easy by nature, not burdened by people, but encountered a rough marriage. The secret of betrayal hidden between the three brothers made the relationship even more tense. At the same time, the mainland super firefighter Haiyang (Hu Jun) came to report. As a "new recruit" of the Hong Kong Fire Department, he encountered "veteran" Pei Zong (Simon Yam)'s open and covert difficulties, and he himself had an unsolvable knot in his heart. The crisis finally came, the power station exploded and caught fire, and Hong Kong fell into an unprecedented darkness. A group of people were trapped in the sea of fire, their lives hanging by a thread. Firefighters walked into the pitch-black darkness and fought against the deadly smoke. They had to save people and deal with the struggle between brothers. There were also orders from the top leaders to ensure safety. Was it "one life for one life, save one life" or "obey the order and put the overall situation first". This fire was not only a rescue, but also a redemption between brothers, waving away the smoke that blinded their minds caused by the inner demons.