No Mercy (2019)

Revenge plot
although No mercy is much heavier for some of the thematics it dives into, it's also much more explicit

Similarities:
- A strong female lead in an action packed movie taking bloody revenge without minding her own wellbeing.
- Lots of fighting blood and violence

Differences:
- human trafficking and abduction with sexual abuse of the abduckted (read the taggs before watching)
- FL trying to safe the abducted younger sister
- no law enforcement authories involved

Both a revenge and rescue story with a skilled main character with a hidden/secret past.

I recommend this both drama because , Male lead and Female lead
try to solve problem
In one drama explosion and another student murder/suicide

Both movies have a strong female lead who is good at beating/killing people and has a mysterious past.

Same premise of someone fighting to save a child who has been taken, however in The Man From Nowhere it is his younger neighbor and not a younger sibling.

Both dramas revolve around sisters taking revenge on the bullies and abusers of their younger sibling. Both leads have a very similar personality and both go to extreme length to accomplish their deeds.

A ordinary MC with a mysterious past on the hunt for people that have kidnapped their loved ones, in No mercy's case a sister and Unstopabble his wife. A must watch if you liked either show.

Both about an older sister trying to protect/save their younger sister from a kidnapping.

Description of Manhole:
A serial killer has been terrorizing a neighborhood in Seoul, and in the span of 6 months, 10 people have disappeared without a trace. He uses a manhole to trap his victims. His latest abductee is Soo Jung, a 14-year-old girl, and her older sister Yeon Seo is desperate to find her before time runs out.