Into The King: Eternal Monarch? These Top Best Parallel World Korean Series!

The King: Eternal Monarch wasn’t just a love story. It was a mind-bending journey through time, fate, and parallel worlds. With its grand romance and alternate universe twists, it gave viewers something deeper — a “what if” story that made us think about choices, timelines, and love that defies all logic.

If you're still missing the thrill of crossing between worlds, these new Korean dramas from 2025 and 2026 are ready to fill that gap. They take on parallel timelines, reality shifts, and bold sci-fi storytelling — all wrapped in emotion, suspense, and beautiful visuals.

Here are the top best parallel world Korean series in 2025/2026 that fans of The King: Eternal Monarch will absolutely love.

1. Twilight Door (2025) — Romance/Fantasy

A mysterious elevator in an old university building takes a student into a world where she never lost her twin sister. Every night, the doors open. But each visit changes both timelines. Deeply emotional and full of soft heartbreak.

2. The Mirror Code (2026) — Sci-Fi/Mystery

A police detective finds a mirror that leads to a universe where his wife — who died five years ago — is still alive. But he’s not supposed to be there… and someone wants him gone. Smart, twisty, and packed with emotion.

3. Another Me (2025) — Thriller/Drama

A successful doctor discovers she’s being stalked by someone who looks exactly like her. Turns out — it is her, from a darker version of reality. What follows is a cat-and-mouse game between two lives that should never cross.

4. Switch Point (2026) — Sci-Fi/Romance

Two college students in parallel universes begin communicating through a shared dream. As their lives begin to overlap, they face a choice: stay in their worlds or risk everything to meet. Soft, beautiful, and haunting.

5. Kingdom Reversed (2025) — Historical/Fantasy

A modern-day historian is pulled into a Joseon-era kingdom where history happened differently. There, she meets a crown prince who knows about her world — and has been waiting. Blends palace politics with parallel world twists.

6. Shattered Sky (2026) — Action/Sci-Fi

A brilliant hacker cracks a code that opens portals between realities. But each jump fractures his memory — and the woman he loves only exists in one world. High-stakes, fast-paced, and visually stunning.

7. The Other Line (2025) — Mystery/Romance

A quiet librarian keeps receiving handwritten letters — from herself in another universe. As she follows the trail, she discovers a world where she made one different choice… and everything changed. Soft mystery with strong emotional pull.

8. Parallel Hearts (2026) — Romance/Drama

Two people fall in love — but they don’t exist in the same timeline. Every time one of them moves forward, the other moves backward. Their love is real, but the world won't let it be easy. Heartbreaking and beautiful.

9. Crossfade (2025) — Sci-Fi/Youth

In a future where teens can visit alternate versions of themselves, one high schooler finds a version of his life where his brother never died. But staying there comes at a price. A unique blend of sci-fi and youth drama.

10. Echoed Lives (2026) — Drama/Fantasy

A woman wakes up every week in a slightly different version of her life — different job, partner, even memories. She begins to question which world is real, and what choice trapped her in this loop. Introspective and tense.

11. TimeSplit (2025) — Romance/Action

A soldier from one timeline and a doctor from another end up in a shared space that exists between their worlds. Together, they try to stop a collapse between dimensions — while falling for each other. Think The King meets Signal.

12. Zero Point (2026) — Sci-Fi/Mystery

A group of strangers wake up in a lab with no memory — and find out they’re all versions of the same person, pulled from 12 parallel worlds. They must solve a mystery before their realities merge. Smart, high concept, and totally gripping.