"I had the same experience as Mei. I used to be a dance lover but my parents wanted me to become a doctor in the army. They locked me in the room and I even broke the window so I could go to dance class then. I tried very hard to persuade them but failed," recalls Fan. "I never expected that I would dance on stage one day."

Zhao Yuanlong, a 62-year-old retired solider, was enlisted during China's border war with Vietnam in 1979.

"For young people then, joining the army was the most honorable job and art was considered frivolous," says Zhao, who plays the role of Mei's father, an official from the army. "The war was cruel. It not only made people give up their dreams but also deprived many young men of their lives."

The performance is full of nostalgic elements, including the patriotic songs, army suits and zhong zi wu, a dance form popular during the "cultural revolution" (1966-76).

According to Zhao Shuai, who has done research about older people in China, there were more than 200 million people age 60 and older in China by the end of 2013, accounting for nearly 15 percent of the population. He found that around 83 percent of people in that age group engage in some sort of physical activity.

He also says that lots of old people in China are enthusiastic about "square dances" in public spaces around the country in the mornings and evenings. However, the national phenomenon has stirred up some controversy: The loud, amplified music irritates some neighbors, while other critics say this activity takes up too much public space.

"We want to lead a trend, which has old people dance in theaters," says Zhao, who plans to take the show touring in the country. "I hope the old people can make their dancing shows, which is not just a good way to stay healthy but also enriching their retired lives."