A quiet, steadfast stuntman Jaeyeon strictly follows his principles. He's assigned to train Doha, an idol cast in an action movie. But Doha is unruly, proud, and refuses to listen. Still, Jaeyeon is just as stubborn. He puts a stop to Doha's tricks and shortcuts without mercy, and the two inevitably become bitter rivals. Then one day, their usual bickering is captured in an idol behind-the-scenes video, and Jaeyeon suddenly gains unexpected popularity… marking the beginning of a situation neither of them saw coming.