Posing as her twin brother in a boy band, a young woman wins the heart of her bandmates and fans, all the while searching for her long-lost mother.
When Go Mi Nam is sent to the United States for corrective eye surgery, Manager Ma begs Go Mi Nyeo to dress as a boy and take her brother's place.
Mi Nam (as Gemma will now be referred to) wakes after a party to realize that she has kissed one of her band mates but can’t remember which one. More silliness ensues as Mi Nam attempts to set things right with Tae Kyung.
Having found out her true identity, Tae Kyung wants to kick Mi Nyeo out of the group, but she insists on staying until she finds her moth
The band prepares for a performance at the music festival, where they meet Tae Kyung's mother and Yoo He Yi, a singer-actress with a fake personality.
Mi Nyeo spends time bonding with Shin Woo and Tae Kyung. Her aunt's arrival forces Mi Nyeo and Tae Kyung to make a difficult decision.
Mi Nyeo is unsettled after one night in Tae Kyung's room. He Yi finds out Mi Nyeo's secret and uses it to bribe Tae Kyung into being her boyfriend.
Unable to perform Tae Kyung's song satisfactorily, Mi Nyeo takes a trip to her father's hometown for his memorial ceremony. Tae Kyung joins her for the short retreat.
Tae Kyung, Mi Nyeo, and He Yi shoot a music video together, which make unspoken feelings rise up to the surface. Jeremy lets Mi Nyeo in on his secret bus and Tae Kyung confronts his distant mother.
When Mi Nyeo loses her ribbon pin, Tae Kyung realizes how much she cared for something he gave her. He confronts her on whether she likes him or Shin Woo best.
He Yi threatens Mi Nyeo about her secret, forcing Mi Nyeo to reveal her true identity to all the band mates and the press.
Now that the ANJells know Mi Nyeo's secret, they decide to protect her. Tae Kyung's jealousy rises as Shin Woo continues to treat Mi Nyeo as his girlfriend.
During a photo shoot, He Yi plays around with Tae Kyung and Mi Nyeo's feelings. She dresses Mi Nyeo in a gown for Shin Woo and Tae Kyung to see.
Mi Nyeo must continue the ruse as her brother and as Shin Woo's girlfriend. Tae Kyung tests her to find out if she truly likes him or not.
Hwa Ran's close relationship to Mi Nyeo's deceased father creates trouble for Mi Nyeo and Tae Kyung's blossoming relationship.
A trip to Japan forces Mi Nyeo and Tae Kyung to confront the truth about their parents' past. Mi Nam rejoins the band when they return to Seoul.
Mi Nyeo gets ready to leave for Africa. Tae Kyung sings one last song for her