Moon Chae-won

Once known as the frontman of the rock band Ambulance during his college days, Seung-min now lives a quiet life running a small instrument shop. One day, his legendary first love Bo-na, the girl he never even had the courage to confess to before she suddenly disappeared, unexpectedly reappears in his life. From that moment on, Seung-min's heart begins to race again. But as old feelings resurface, he finds himself trapped in an awkward predicament: a secret he must never let his first love discover… no matter what.

A train ride brings two unlikely souls together as Bae, a committed partner of a serious 10-year relationship, sees her world turned upside down by the charming playboy Kim. Seated together on a business trip from Seoul to Busan, the two find themselves on an adventure to remember.

After the death of their father, two siblings are raised by their father's best friend. However, when one gets kidnapped just before her wedding, the other rises against the Manchus.