The summary of the main content of 'The Destroyed City' in '20,000 Miles Under the Sea'?

The Ruined City in 20,000 Miles Under the Sea was a science fiction novel that described a cursed city discovered by humans in the process of exploring the ocean. This city was built by a group of scientists who used the most advanced technology to build an underwater city in an attempt to solve the energy and environmental problems facing mankind. However, when the humans approached the city, they found that the city was slowly being destroyed. The city's infrastructure was corroding, and various strange phenomena were happening inside the city. Humans began to realize that the city was controlled by a mysterious supernatural force that seemed to be related to some substance in the ocean. In order to save the city, humans must explore the city to find the source of this mysterious power and solve the city's problems. In the process, humans faced many challenges and dangers, but they finally found the answer and successfully saved the city.