Trucker couple Li Mei and Zhou Erqiang were driven to a dead end by an unscrupulous shipper, and late at night they mistakenly entered the Tonggu Tunnel, where a truckload of watermelons unexpectedly opened up a passage between ancient and modern times. Pingyang Ferry at the border of Da Qi suffered a severe drought and ran out of grain, while teenage general Gu Changting defended the isolated city to the death. The couple drove their semi-trailer back and forth across the two realms, delivering water, grain, and equipment, using modern supplies to feed an army of half a million and step by step rewriting the destiny of the border.