The Defects

Why It’s Similar: Combines medical drama, power plays, and revenge.
Tone: Dark, strategic, and suspenseful.

Despite being very different on the surface, both dramas touch on a few similar deep themes:
Abuse of power (Kim Se Hui’s cruel experiments vs. court elite manipulating the fates of harem women)
Justice and revenge (Kim A Hyeon’s revenge vs. uncovering Princess Huai Si’s motives)
Women as victims and fighters (Both explore how women are wronged by the system and either seek truth or revenge)
Corruption hidden behind a respectable image (A respected doctor vs. a respected court)

SKY Castle and The Defects both offer gripping, socially charged takes on South Korea’s elite education system. With sharp commentary on privilege, academic obsession, and parental pressure, these dramas peel back the layers of a system that rewards status over sincerity. Both feature strong ensemble casts, complex female leads, and a suspenseful tone that blends drama with mystery. If you're drawn to stories that expose the dark underbelly of success and the emotional toll of perfectionism, these two shows are a compelling, thought-provoking watch.

If you love intense drama with rich people doing VERY shady things, Penthouse and The Defects are right up your alley. Both shows dig into the dark side of South Korea’s elite especially how far parents will go to make their kids succeed. There’s mystery, revenge, and plenty of over-the-top twists, all set in a world where status means everything. With strong (and often ruthless) female characters and a sharp take on academic pressure, these dramas are dramatic, addictive, entertaining and often gut wrenching.

The plot centers on a group of people who find their ordinary lives thrown into chaos due to a family tragedy. They monitor criminals 24 hours a day and rescue potential victims before the crime is committed. They also embarrass corrupt state prosecutors and make sure that criminals are punished for their crimes. This TV show illustrates the current society where the simple rule of going to jail if you break the law no longer applies to those in power. Illustrating the tragic lives of the Watchmen group who channel their anger and grief into fighting for justice, “The Guardians” will have stylistic action scenes and a thrilling plot.

Both dramas have as main focus the revenge of children who in the past was abused by adults.
In particular in both dramas the children were treated as objects.

This is more of a warning than a rec, TBH - for those who are NOT into misery porn. These dramas appear to be filled with it (I'm certain on Namib's part, I've already watched it, getting a very similar vibe from The Defects, based on the first two eps).

The plots don't have much in common, except for the anguish element - each of the victims/vigilantes in The Defects seem to be in constant pain (and mental distress) from their experiences, much as the MC of Namib. In both cases, the people responsible for it are people who are supposed to be the characters' best help, parents or legal guardians.

So just an advice - if you're really NOT into watching people suffer through no fault of their own as a main plot device, consider giving these two dramas a pass.

In both dramas the revenge is the main focus. Both the revenge take place after years.
Both dramas have the same dark vibes.

In both drama the children were treated as objects and after many years they carry on revenge.
Kill It! is more romance focused.

Both dramas focus on “the perfect child”, adults become monsters trying to reproduce genius kids and they don’t care for the casualties
Both also have one kind adult that “kidnaps” the kids to save them

Both have the crime side, a group of friends as if they were brothers also the fl is strong and genius