It's been years since Boa returned to Seoul. As a popular choreographer, she's been in America and Japan for a long time, but with a slowing of business, she decided to return to South Korea. 

The city had evolved, and in Seoul, she saw groups of dancers performing publicly, flash mobs. It was interesting, how coordinated and in-sync the mobs were. There seemed to be multiple groups, rivalries.

Teaching at the prestigious Shinhwa Academy of Dance, she finds that even some of her students are well-aware of these flash mob groups.