In ancient times, a severe drought lasted for three years, water sources dried up, and the common people fell into dire straits. The old prince unexpectedly traveled through time to a modern restaurant, where he was shocked by novel things such as soda and tap water, mistakenly believing them to be fairy spring water. He brought people along to ask for help, and shopkeeper Su Nian, thinking it was a film crew shooting a drama, generously donated water to help. After learning their true plight, she softened her heart and extended a helping hand, using modern water sources to save ancient disaster victims. A mouthful of tap water connects the ancient and modern times, warming the suffering common people in a turbulent world.