 Welcome to Spotlight Advanced. I'm Liz Wade. And I'm Colin Lauver. Spotlight uses a special English method of broadcasting. It is easier for people to understand no matter where in the world they live. Zhengxi is sleeping 10 metres underground. He wakes up to the sound of pots and pans clanging. His neighbours are using the kitchen early again. But he does not mind. Time is not the same in Beijing's underground city away from the sun. She dresses quickly in his small room. It is so small that he must duck to keep his head low when he stands. He gathers a suitcase full of Buddhist prayer beads. Above the ground he will sell these beads on a street corner. But now he must begin the long trip to the surface. He ducks through short hallways. He drags the suitcase up cracked stairs. He passes other small rooms like his full of people. Finally, he reaches a door that opens to the street. Cars rumble past him. It is the first time he has felt fresh air all day. All around Beijing, thousands of doors like this are opening. People like Xi are coming from their underground homes. They come up to clean people's homes. They come to cook in restaurants. Then, when their jobs are done, they go back to these doors. Together, they disappear underground. It is like they were never there. Sim Qiyin is an artist and photographer. She followed the lives of some of the people like Xi. She told their stories to the world. Together, the people of Beijing have a name for these underground people. They are called Shusu. In English, the Rat Tribe. Today's spotlight is on the Rat Tribe of Beijing. Beijing is one of the largest cities in the world. Over 20 million people live there. It is also the capital of China. It is the country's cultural centre. Because of this, there are many opportunities for work in Beijing. People travel from all over the country to live in Beijing. They move there to follow their dreams. But many of these people are not wealthy, and housing in the city is extremely expensive. Some people do not have permits to work there, so they must find homes somewhere else. Many settle in the basements and tunnels of Beijing. They become members of the Rat Tribe. Rooms underneath the city are very inexpensive. They cost about half as much as the rooms above ground. They are not good rooms. Many are very small. People living there must share toilets and kitchens with many different households. These rooms were not built for people to live in permanently. Some were not even meant for people. The government of China built many of these rooms as bunkers in the 1960s. These underground structures are where people would go in case of a bomb attack. For a long time, the government of China feared war. They required most buildings to be built with bunkers beneath them. They even built a huge public bunker. Local people call this bunker the Underground City. The Underground City was over 85 square kilometres. But when war never came, owners of these buildings began to sell space for rooms. The government even allowed people to rent spaces in the Underground City. Some of these rooms were meant for people, but some had to be changed. Places meant for food became places where people could stay. Cold concrete rooms changed into cozy living spaces. More and more people moved to Beijing. There was no room for them. So they moved into the bunkers. Today, there may be over a million people living underground. This bunker housing is cheap. But being a member of the rat tribe can be difficult. Living underground can be cramped and depressing. It is difficult to live only by electric light. Li Hao is working to become a photographer-filmmaker. He lives in Beijing's Underground. He told Al Jazeera America... The first basement I stayed at in Beijing was very large. But it was very humid, with a lot of water in the air. After one month, it was still smelly. There was water on the floor from the humidity, and things got moldy. So I moved. Then I found this room. It is about eight square meters for 360 yuan. I have no income, so I live here. It is OK. I do feel uncomfortable here, though. I always feel very tired. Maybe because there is no sunlight here. Many people of the rat tribe also feel a great shame about living underground. They may not share where they live with their families or friends. Some may like their living situation, but their families object. It can cause tension between family members. Zhang Shi is an immigrant from Mongolia, who is a member of the rat tribe. He told Al Jazeera America... My dad visited me a while ago. When he came, I had no time to clean up beforehand. I know he cried that night. He stayed with me. He said, son, this will not do. This place is not suitable for living. But I told him that when I go out, I always look very presentable. Who will know that I live in a basement? Living as a member of the rat tribe is also difficult for another reason. In 2012, it became illegal. Chinese authorities now believe that these bunker rooms are not safe. Many do not have fire escapes. If a basement were to flood, many people would die. Members of the rat tribe are willing to take this risk. But the city of Beijing is not. In 2015, they evicted 120,000 people living underground. Every one of them lost their homes. There was nowhere for them to go. So while there is danger living underground, there is also a danger of having no home at all. Still, most members of the rat tribe do not believe that their situation is permanent. Even if their homes are illegal, they still persist. They plan to save their money until they can purchase a better house. Some wait until they can get a better job. Living underground is one step on a road that leads to a better life. Zhang Qili works in Beijing and lives in a basement apartment. She told the magazine Foreign Affairs. There is no real difference between us and the people who live above us. We wear the same clothes. Our hairstyles are just as funky. The only difference is that they have more money now. When we can afford it, we will also move upstairs. As for Zhang Qili, he continues living in his basement because he has a dream. He wants to be an actor and he believes the best way to do that is to live in Beijing. Living as a member of the rat tribe is the only way he knows to follow his dream. And he will live in his basement room until he finds his way. In a video from Creative Time reports, he says, I do this because I have a dream. To say it out loud sounds almost wishful, but I came to Beijing because of a dream. I am like so many young migrants. We are all seeking to succeed here in Beijing. Only we migrants live in basements. Young people like us, why else would they come to Beijing to live in a basement? They definitely do this because they have dreams. Do you have a dream? What would you do to achieve it? Would you live underground? You can leave a comment on our website or email us at contact at spotlightenglish.com. You can also find us on YouTube, Facebook, Instagram and Twitter. The writer of this program was Dan Christman. The producer was Michio Ozaki. The voices you heard were from the United States and the United Kingdom. All quotes were adapted for this program and voiced by Spotlight. You can listen to this program again and read it on the internet at www.spotlightenglish.com. This program is called Rat Tribe, the story of Beijing's underground cities. Visit our website to download our free official app for Android and Apple devices. We hope you can join us again for the next Spotlight program. Goodbye.