How to describe this drama...
START of drama was little boring lot of exposition to get you into story
MIDDLE of drama was nice to look at and I enjoyed it...
END of drama .... PLANAR/TIMETRAVEL MESS

this drama had few nice action and romance scenes I will remember and I rewatched these scenes few times. Think its worth to see just for them... almost all of these scenes are in middle part of drama.

plot - ML is emperor of korea from parallel world1.
FL is South korea detective from parallel world2[probably our world]

ML manages to travel to another world and meet FL there starts romance storyline which crosses boundary of time and plane and reality.
Add to it traitor uncle of ML which wants become emperor and got same power to cross borders.

genre - romance, plane/timetravel, action, slight myster