The premise of this tv show is good, playing with a "time loop" theme which i believe hasn't been done before. The casts are also good. I don't have any complain of their actings. The scenes however, can be boring sometimes, particularly during the police interrogations. I feel a little frustrated seeing the couple trying to hide the time loop reason and telling lies to avoid being suspects. Some of their actions also bear questions, as they seem not cleverer after many trial & errors. Annoying, to see how the couple plus all passangers couldn't handle the two prepetrators, sometimes, just standing there blank.
As for the music, i don't have any complain. I enjoy both the intro & outro songs. The biggest letdown are, they don't explain why there's a time loop, and more importantly, why only HeYun suffers the agony later. And there is still a plothole in ep2. The couple used the "pervert" reason to get off the bus the second time. That was exactly the same like the first one, where the bus made an illegal stop. And because of that slight delay, the bus needed to stop at the intersection because of the red light, But why didn't it collide with the oil truck like the first time? Instead, the bus exploded on the bridge.