- Title: 어쩌다 발견한 하루 / Eojjeoda Balgyeonhan Haru
- Also known as: A Day Found by Chance / Ha-Roo Found by Chance / Suddenly One Day
- Genre: School, fantasy, romance, comedy
- Episodes: 32
- Broadcast network: MBC
- Broadcast period: 2019-Oct-02 to 2019-???-??
- Air time: Wednesday & Thursday 21:00 (2 episodes back-to-back)
- Original Soundtrack: Extraordinary You OST
Eun Dan Oh (Kim Hye Yoon) is a student at a prestigious academy, but she has a heart condition. One day by chance, she discovers that she and everyone else in her world are actually characters in a manhwa called Secret. Worse yet, Dan Oh is only a minor character in this story and is expected to die soon. Not satisfied with this fate, she decides to forge her own destiny by changing the story's plot and finding her own true love.
- Main Cast
- Supporting Cast
- Lee Na Eun as Yeo Joo Da
- Jung Gun Joo (정건주) as Lee Do Hwa
- Kim Young Dae (김영대) as Oh Nam Joo
- Lee Tae Ri as Jin Mi Chae
- Kim Hyun Mok (김현목) as Ahn Soo Chul
- Jung Mi Mi (정미미) as Lee Jin
- Choi Jin Ho as Baek Dae Sung (Baek Kyung's father)
- Ji Soo Won as Cha Ji Hyun
- Uhm Hyo Sup as Eun Moo Young (Dan Oh's father)
- Production Company: RaemongRaein Co. Ltd.
- Director: Kim Sang Hyup
- Original writing: Moo Ryu (무류)
- Screenwriters: In Ji Hye (인지혜), Song Ha Young (송하영)
- Each night's broadcast is divided into two 35 minute episodes with a commercial break in between.
- Based on the webtoon July Found by Chance (어쩌다 발견한 7월) by Moo Ryu (무류), which was published in 2018 by Daum Webtoon.