Just when things were getting warm and fuzzy between Sunwoo Chan and Song Ha Ran, In Your Radiant Season drops a bombshell. Episode 4 of MBC’s newest romance drama teases a heart-stopping near-car-crash moment — and a hidden trauma that changes everything fans thought they knew about Chae Jong Hyeop’s lovable, carefree character.

In Your Radiant: Drama

Detail	Info
Drama Title	In Your Radiant Season
Network	MBC
Episode 4 Air Date	February 28, 2026, 9:50 PM KST
Lead Actors	Chae Jong Hyeop & Lee Sung Kyung
Characters	Sunwoo Chan & Song Ha Ran
Genre	Romance Drama
Supporting Cast	Oh Ye Ju, Kim Tae Young, Lee Mi Sook
Where to Watch	Viki (International) / MBC (South Korea)

What Happened in Episodes 1–3?

In the previous episode of In Your Radiant Season, Song Ha Ran — a woman who has closed herself off as though trapped in a long winter — gradually began to open her heart to Sunwoo Chan, a man who lives each day like an exciting summer vacation. She accepted his offer of a “three-month neighborhood friend trial,” and as the two spent more time together, their relationship began to evolve warmly.

It was sweet, slow-burn K-drama goodness. Then came Episode 4.

Episode 4 Preview — Trauma, Near-Crash, and Family Secrets

In newly released stills from the upcoming fourth episode, Song Ha Ran unexpectedly witnesses Sunwoo Chan experience a trauma response while driving her somewhere. After receiving a call from Kim Na Na (Lee Mi Sook), Sunwoo Chan is behind the wheel when the sound of a motorcycle horn causes him to suddenly experience severe tinnitus and blurred vision — nearly causing a crash. He ultimately pulls over and apologizes to the motorcyclist with a bow, while Song Ha Ran watches with visible concern, seemingly startled by this new, vulnerable side of him.

That scene alone is enough to send fans spiraling. Who is Sunwoo Chan — really? And what exactly happened to him?

The Subplot Getting Everyone Talking

Meanwhile, in a separate storyline, Song Ha Dam (Oh Ye Ju) introduces her boyfriend Cha Yoo Kyum (Kim Tae Young) to her family for the first time. He arrives nervously with flowers — but freezes the moment he spots Kim Na Na. Her steady gaze in return raises an immediate question: what is the history between these two, and will she approve of him marrying her granddaughter?

Two storylines, one explosive episode. K-drama fans have not been sleeping.

For more K-drama updates, episode previews, and Korean entertainment news, visit TechnoSports Entertainment.

FAQs

Q: When does In Your Radiant Season Episode 4 air and where can I watch it?

Episode 4 of In Your Radiant Season airs on February 28, 2026 at 9:50 PM KST on MBC — international viewers can stream it on Viki with subtitles shortly after the Korean broadcast.

Q: What is Chae Jong Hyeop’s character’s trauma in In Your Radiant Season?

In Episode 4, Sunwoo Chan experiences severe tinnitus and blurred vision triggered by a motorcycle horn while driving — revealing a hidden trauma that shocks Song Ha Ran and adds a deep, mysterious layer to his otherwise cheerful personality.