Episode 25 recap: The First Brigade discovered valuable cultural relics, and Sha Kai was threatened by Chen Yuanlong.

The First Brigade discovered valuable cultural relics, and Sha Kai was threatened by Chen Yuanlong.Yao Wa voluntarily called Zhang Biao "dad," and Zhang Biao was overjoyed. He hugged Yao Wa tightly, and Yao Wa made a walnut pendant for Zhang Biao to wear around his neck. Zhang Biao excitedly thanked Wang Lanzhi and Yao Wa, making himself feel happy.

He said that after the railway was repaired, he would take them all on a train to see the beautiful scenery of their homeland. The foundation of the First Brigade's roadbed has all passed inspection, and the next step is to lay the tracks.
Everyone is full of enthusiasm and eager to work, striving to meet the deadline. Due to the complex terrain in this area, Ye Lan requested that everyone dig deeper when building bridges to prevent the roadbed from being washed away by heavy rain.
 Everyone agreed to follow her arrangement. The track laying is currently in progress, but the subsequent tracks have been delayed in delivery. Sha Kai informed everyone that it had been raining heavily these days, and the trucks carrying the tracks were stuck.
 They didn't know how long they would have to wait here. Sha Kai suggested taking a break instead. However, Zhang Biao disagreed with taking a break because once people take a break, their focus would be lost. Zhang Biao was eager to meet the deadline and went to the battalion commander to request the tracks.
 The battalion commander said there was no way to transport the tracks by land. Zhang Biao suggested using waterways instead, but the river was too shallow and had sharp turns, making it impossible for large ships to navigate. Zhang Biao decided to try using bamboo rafts to transport the tracks. Sha Kai thought he was being unrealistic. Zhang Biao insisted on trying to transport the tracks using bamboo rafts. So, Zhang Biao, along with soldiers from Wuzhi and Sichuan, started transporting the tracks by water. Luo Xiangqian and Ye Lan led a team to dig a culvert.
 During the construction, Ye Lan discovered a fossilized turtle and asked everyone to stop and protect the cultural relic. Luo Xiangqian was dissatisfied because this so-called relic was delaying the construction schedule. Ye Lan took him to meet with the battalion commander. The battalion commander supported their decision and sent Professor Zhang, a renowned scholar, to lead a team to conduct further investigations. Professor Zhang predicted that there would be astonishing discoveries in the Huangshan Creek based on the initial survey.
 As expected, Professor Zhang personally conducted excavations and discovered human skulls. Professor Zhang planned to take the excavated relics back to Chongqing for further testing. In order to reward the First Brigade for discovering and protecting the relics, Professor Zhang stated that he would apply for funding to help them repair the bridge.
 Everyone was very happy upon hearing this. The excavation team led by Luo Xiangqian and the track-laying team led by Zhang Biao successfully completed their missions. The Huangshan Creek Bridge was opened to traffic, and the track laying was successfully finished.

The first squadron immediately burst into cheers. Shakai wandered into the town, where Chen Yuanlong greeted him and invited him to have a drink together. He mentioned that Sui Li was also there, which piqued Shakai's interest. Chen Yuanlong mentioned that he had a friend from Chongqing who he wanted to introduce to Shakai. The friend Chen Yuanlong introduced was none other than the leader of the secret agents, Li Muyang. Li Muyang asked Shakai about the progress of railway construction and learned that the Chengdu-Chongqing Railway's Yongchuan section was scheduled to open on July 1st. Upon hearing this, Li Muyang started scheming.

The skull discovered in the Huangshan Creek, after being studied by experts in Beijing, turned out to be from the Ziyang people from 35,000 years ago. Its cultural value was equivalent to that of the Beijing Shan Ding Cave people. This significant discovery earned praise for the first squadron and even made it into the newspapers. Li Muyang assigned tasks to his subordinates, instructing them to cause a disturbance when the Communist Party's Yongchuan Railway opened, preferably one that would have a global impact. He also wanted to expedite the process of turning Shakai into a double agent. Chen Yuanlong invited Shakai for a drink and lavished praise on him, while Sui Li served him food and drink with sweet words. Shakai quickly became intoxicated and agreed to whatever Chen Yuanlong asked of him. Chen Yuanlong pretended that he needed railway construction blueprints for the supply station and asked Shakai to help him obtain a copy.

Shakai readily agreed and secretly searched for the blueprints. Zhang Biao noticed Shakai's strange behavior. Shakai handed the blueprints to Chen Yuanlong, who gave him a stack of money as his reward. Shakai found it strange, and Chen Yuanlong revealed his identity as a Kuomintang secret agent to Shakai. Filled with fear, Shakai was threatened by Chen Yuanlong, who warned him to ensure his participation in the Yongchuan opening ceremony; otherwise, he would hand over the blueprints to the Communist Party. Helpless, Shakai had no choice but to agree to do his best.

The first squadron was discussing who should attend the opening ceremony. Everyone recommended outstanding workers who had shown enthusiasm. As for the technical staff, they all suggested Ye Lan. However, as soon as Ye Lan declined, Shakai expressed his desire to go. He emphasized that he wanted to go for educational purposes and also mentioned that he hadn't seen his uncle in a long time and wanted to take this opportunity to meet him. When Chen Yuanlong learned that Shakai had secured a chance to attend the ceremony, he pressured him to bring a timed bomb with him. Otherwise, he threatened to report Shakai as a Kuomintang spy. Forced into a corner, Shakai reluctantly agreed.