Only in Korea would the invention of an alphabet be the stuff of a conspiracy thriller — secret societies, palace murders, a king playing the long game against his own aristocracy. That's not embellishment for TV, either: when King Sejong introduced Hangul in the 1440s, easy literacy for common people genuinely threatened the elite's monopoly on the written word. Tree with Deep Roots (뿌리깊은 나무) takes that real political tension and builds a murder mystery on top of it — and fifteen years after airing, it's still the title Korean drama fans hand to anyone who says historical dramas aren't for them.

If you've been following our Korean-language series — learning Hangul in a weekend, reading your first story — consider this the dramatized origin story of the alphabet you just learned.

What it is

Tree with Deep Roots is a 24-episode SBS series from 2011, adapted from Lee Jeong-myeong's bestselling novel. The premise: in the days before Sejong unveils his new script, scholars of the royal research institute start turning up dead inside the palace. A young royal guard with a childhood grudge against the king investigates the serial murders — and the trail leads to a shadowy faction that sees the new alphabet as an existential threat worth killing over.

Three things made it a classic:

  • Han Suk-kyu's King Sejong. Film star Han Suk-kyu plays the king not as a bronze statue but as a haunted, foul-mouthed, brilliant man wrestling with his father's bloody legacy — a portrayal that reset how Korean TV writes "the great king." He took home the top prize (daesang) at that year's SBS Drama Awards for it.
  • The alphabet is the MacGuffin — and it earns it. The show treats "28 letters anyone can learn in days" as a weapon of mass empowerment, and walks you through why the design is revolutionary. It's the rare thriller where linguistics scenes carry real suspense.
  • It plays fair as a mystery. Jang Hyuk's investigator and Shin Se-kyung's court maid anchor a plot that twists hard but coherently — the show rates 8.0 on IMDb largely on the strength of its writing.

The history is dramatized, to be clear — the murders and secret society are fiction wrapped around the real creation timeline and the real class politics of literacy. Treat it as a thriller about history, not a documentary.

Where to watch

Tree with Deep Roots streams on Rakuten Viki (free with ads) and the Kocowa channel on Amazon, depending on your region. English subtitles are solid — and as a bonus, the show is a workout for your ear on the formal speech levels we covered in our banmal vs. jondaemal explainer; court Korean is the honorific system turned up to maximum.

If you want more Sejong

  • The King's Letters (나랏말싸미, 2019) — a film take starring the great Song Kang-ho (Parasite) as Sejong, focusing on the monks who may have aided the alphabet's creation. Worth knowing: that framing drew real controversy in Korea on release, since the "monk Shinmi" theory is a minority historical view presented quite confidently. Watch it as one interpretation, not the record. It streams free with ads on Tubi and other platforms in the US.
  • King Sejong the Great (대왕세종, 2008) — the full 86-episode KBS biographical epic, for viewers who finish Tree with Deep Roots wanting the whole reign, not just the alphabet arc. A commitment, and paced like classic old-school sageuk.
  • A modern companion piece: the same "genius king vs. entrenched elite" energy runs through most palace dramas — if you bounced off traditional sageuk before, our Alchemy of Souls fusion-sageuk guide maps the lighter end of the genre.

The honest take

Tree with Deep Roots is 24 episodes of dense, dialogue-heavy political drama — it asks more of you than a rom-com, and the first two episodes (a childhood prologue heavy on court politics) are the steepest part of the climb. Push through to episode 3; that's where the mystery engine starts and doesn't stop. And if 24 hours of television about an alphabet sounds absurd — that's exactly the pitch. No other country would make this show. That's the reason to watch it.

This article is independent editorial by Seoul Glow. We have no affiliation with any broadcaster or platform mentioned. Streaming availability is as listed by aggregators as of August 2026 and varies by region.