Best friends Ailee and f(x)'s Amber will take viewers along on a trip to Jeju Island for MBC Music's 'Wonderful Day' ('One Fine Day')!

Ailee and Amber, who never got to vacation together due to their busy schedules, were whisked off on a 6-day vacation to Jeju Island last month. Since they're both from the United States, the girls planned their trip like tourists and were always full of energy with their dance-off and more.

The 6-episode special will air on December 30 at noon KST!