Train

The base concept is different. In tunnel it's about time travel, while in Train, it's about traveling between alternate realities. Even so, there are numerous similarities, which you'll recognize if you watch both shows.

Overall, it's a mysterious show that stays interesting throughout.

I didn't expect to like this series at all, but decided to watch it as it has the same lead actor as "Psychopath Diary". I wasn't disappointed and found this show entertaining.

This show has a relatively unique plot (similar to "Tunnel" or "Signal" but this time across universes). Unlike the American "Fringe" which also deals with multiple universes, this series stays very human and character-driven, and doesn't go off into a technical apocalyptic dystopia like so many US shows.

The lead character cast is strong and their performances are outstanding.

I like how they made the point of little decisions, when accumulated, leading us on vastly different life paths.

The show does suffer from a few unfortunate tropes though:

• Endless flashback to literally the same memories, and overlapping episode endings/beginnings. I found myself becoming good friends with the "skip" button. There's probably a few episodes worth of literally 100% repeated footage.

• The standard thriller tricks of a character going to explore abandoned buildings at night, in the dark, after learning that the armed criminal is there, without telling anyone where they're going or asking for backup. This cliche appears so much because that's what normal humans apparently do, right?

• A bit over-dramatic for my tastes at times. These endless hard stares, criminals monologuing for minutes on end before pressing the trigger, protagonists turning their backs on wounded enemies to cry and hug so the enemies could attack them again or escape, statements full of pathos, it's all here.

Overall, an excellent experience which could have been made much tighter by eliminating 90% of repetitions.

I'm not really a sci-fi fan, so I wasn't expecting much when I started this drama, but I was hooked from the start.

The drama moves smoothly, avoiding many plot holes that most of these dramas fall in, you'd expect you found one and it turns out to be part of the plan or an unexpected plot twist.

I've known Siyoon first from Psychopaths' Diary, so it took me the first 4 episodes to not laugh everytime he has a serious expression, but he's a good actor and did well in this role.

The only part I didn't like much was how rushed the ending felt. They left unexplained bits that don't affect the overall plot, but still made the last 20 minutes feel like the director was saying "You get the idea now, you'll figure it out". Which isn't so bad, it might have dragged a bit otherwise, so all in all, it's one of the best shows with that idea.

I must admit that I was confused during the first five or so episodes but was intrigued enough to stay with it.

I am happy I did because the story began to unravel and make sense after that. Much suspension of disbelief is required but then again, this is a sci fi/fantasy show so a lot of creative license was used.

Actors turned in good performances. I last saw the female lead as half of the second couple in Weightlifting Kim Bok-joo. Male lead in this show was very convincing as good cop/bad cop. This show is recommendable to those who love suspense, crime, whodunnit shows.

12 episodes were well-utilized. The team thought well enough not to force 16 episodes out if this.

This was one of the first KDrama's I have watched while it aired, and let me just say that every episode kept me on the edge of my seat, and I was SO disappointed having to wait each week for the next two episodes! Yoon Shi Yoon is quickly becoming a favorite actor of mine; he has quite the range and this really showed when playing the two different versions of the Seo Do Won. He had a similar acting experience in "Your Honor," where he played twin brothers, but this show and these characters were much better in my opinion. The plot is complex but well paced and understandable, and much better done than "The King: Eternal Monarch" which had a similar premise but was executed in a much more confusing manner. This is also one of the first KDrama's that I have watched that hints at/needs a second season - very badly! Overall this was a very enjoyable watch with great acting, well developed characters, and an addictive plot.