The Merciless

Both feature a cop going undercover within a notorious criminal group, only to end up getting too involved in a friendship/brotherhood with one of the criminals

- the tone is the same
- gangs and action packed
- the cinematography and visual effect pretty much the same
- betrayal and loss on both sides
- emotionally moving
- Forgotten has more narrative switches
- Forgotten includes redemption arc, while Merciless is kind of leaving you hanging.
Forgotten is a better movie overall, but I think that this duo from Merciless carried the movie well, and definitely is worth it to watch just for their chemistry. Of course, except for the whole plot and vibe that is similar to the Merciless.

THE BROMANCE is attractive just like The Devil Judge. The Merciless' main character is also well written he is not like Ga On. I think Ga On's character is not developing much throughout the series.
Also you'll like this if you like Vincenzo too.