A natural disaster puts both a nearly complete railway tunneling project and many lives in danger. The main character Hong, an explosives engineer and the rest of the railway crew are on a rescue mission while time is running out. The movie was shot in Karst areas, capturing the spectacular views of Shuanghe Cave, one of the longest underground cave systems in the world. The technical details of explosives engineering, tunneling engineering and rail engineering look authentic and convincing. All the characters are well developed and together tell a great story. The free climbing towards the end is amazing and heartfelt, and I commend the actors for their tremendous efforts in making the scenes look legit. All in all a must see action movie in 2021.
