The grand entry of Gu Jun-pyo, Yoon Ji-hoo, So Yi-jung, and Song Woo-bin as they are swarmed like idols by the student body. The First Conflict:

The cliffhanger: Ji-hoo, the quietest F4 member, secretly helps her — planting the first seed of a complex love triangle.

The series introduces , a hardworking girl from a modest family who runs a dry-cleaning business. Her life changes when she delivers laundry to the prestigious Shinhwa High School and saves a student from jumping off a roof due to intense bullying by the F4 .