Alternate Universe or Timeline

Magical acupuncture needles that take you back and forth from the past 

What really happened all those centuries ago?

Past and present, united by the same cop and serial killer

What really happened to them all back then?

Crossing between two worlds with alternate histories

What happens when you get sucked into a comic book world?

Are you dreaming of the past or are they dreaming of the future?

The next generation unraveling the mysteries of the previous one

How did an alien get stuck in Joseon?

How on earth did Ha Ni of 2000 become the Ha Ni of 2020??

We've got almost 20 years of one family's particular drama to mine

Can't have a reincarnation drama without an alternate storyline

Hey look! A South Korea with a king!

Drawing out the mystery of who is married in the present long after it's become obvious and the fake outs are just ridiculous

The 'who's the husband' mystery got real old real fast

Past and present playing out at the same time - and occasionally changing (oops) 

What's a man from 2018 doing in 1988?  Is he dead? Dreaming? Does it matter?

Flashes of past lives and spirits who are still around all these years later

Body swap shenanigans across dimensions

Unraveling everyone's backstories little by little

Best not to dwell too much on the time travel logistics, and more just focus on happily making the future a better place

Putting together the pieces from various lives

Change the past, make things worse in the present

Just what is this destiny that's tying them together for 300 years?

Trying to change the past - in all the ways that really matter

Original timeline, new timeline - changed for the better?

Why do all these people in new Jeoson look the same as those in Joseon?

Hard to keep all the timelines straight when you keep changing things

Change the past, change the present

Two timelines a month apart, plus multiple iterations of the future