The 2023 South Korean television series Crash Course in Romance became an international hit by blending high-stakes academic pressure with a grounded romantic comedy. Directed by Yoo Je-won and written by Yang Hee-seung, the tvN production follows the unexpected collision between a former national athlete running a side-dish shop and a celebrity mathematics instructor within the cutthroat world of private education.
Understanding who brought these characters to life requires looking past the primary billing. The series relied on a carefully curated ensemble of veteran actors, trusted character performers, and rising young talent to navigate its tricky mix of lighthearted romance and dark mystery elements.
The Main Duet: Haeng-seon and Chi-yeol
At the core of the narrative stand two vastly different professionals forced into an unlikely alliance by circumstance and appetite.
Jeon Do-yeon as Nam Haeng-seon
Award-winning film and television veteran Jeon Do-yeon stars as Nam Haeng-seon, a former national handball player turned busy owner of the Nation's Best Banchan shop. Haeng-seon put her athletic dreams on hold to care for her disabled younger brother and her adopted niece. Jeon infuses the character with physical warmth, steadfast optimism, and fierce protective instincts, anchoring the show's emotional core.
Jung Kyung-ho as Choi Chi-yeol
Playing opposite Jeon is Jung Kyung-ho as Choi Chi-yeol, a star mathematics instructor at a premier private institute known as The Pride Academy. Chi-yeol commands massive wealth and celebrity status but suffers from severe eating disorders and chronic exhaustion. Jung portrays Chi-yeol's sharp professional exterior alongside his vulnerable, neurotic private life, capturing the heavy toll exacted by Korea's hyper-competitive hagwon culture.
The Extended Family and Support System
The daily friction and warmth in Haeng-seon's household and business create the foundation for the central romance.
- Roh Yoon-seo as Nam Hae-yi: Hae-yi is Haeng-seon's hardworking niece and legally adopted daughter. Roh Yoon-seo portrays her with maturity and grounded intelligence, serving as a moral compass among high school peers driven entirely by status.
- Oh Eui-shik as Nam Jae-woo: Jae-woo is Haeng-seon's younger brother, who lives with Asperger syndrome. Oh Eui-shik handles the role with nuance, highlighting Jae-woo's fascination with trains, gentle nature, and keen observational skills.
- Lee Bong-ryun as Kim Yeong-joo: Yeong-joo is Haeng-seon's loyal best friend and business partner at the banchan shop. Lee Bong-ryun provides sharp comedic timing and unwavering support through every scandal.
The Academic Pressure Cooker: Students and Parents
The secondary plotlines dive deep into elite high school classrooms and Tiger Mother rivalries, featuring a standout youth ensemble.
- Shin Jae-ha as Ji Dong-hee: Dong-hee works as Chi-yeol's devoted chief assistant and manager. Shin Jae-ha brilliantly manages a complex character arc that shifts the tone of the series entirely.
- Jang Young-nam as Jang Seo-jin: Seo-jin is a cold, status-obsessed attorney mother who pushes her sons relentlessly toward medical school admission.
- Lee Chae-min as Lee Seon-jai: Seon-jai is Seo-jin's softer-spoken son, balancing academic expectations with a quiet devotion to Hae-yi.
- Kang Na-eon as Bang Su-ah: Su-ah represents the peak of competitive entitlement among students, locked in a fierce grade rivalry with Hae-yi.
Behind the Scenes: Direction and Writing
The success of the series stems from its veteran creative partnership. Director Yoo Je-won brought his signature visual warmth and steady pacing, previously tested on hits like Hometown Cha-Cha-Cha. Screenwriter Yang Hee-seung balanced heavy social critique regarding private education with sharp romantic comedy beats, marking their third successful collaboration.
Frequently Asked Questions
How many episodes are in Crash Course in Romance?
The series consists of exactly 16 episodes, which originally aired on tvN and streamed globally on Netflix between January and March 2023.
Are the episode titles based on mathematics?
Yes. Every single episode title references a distinct mathematical or logical concept, mirroring Choi Chi-yeol's profession and tying academic themes directly into the emotional developments of the plot.
Where was the show filmed?
Production took place primarily around Seoul and surrounding districts in South Korea, using real neighborhood markets and academy settings to mirror the actual private education hubs of Daechi-dong.
Did the cast win any major awards for this project?
The ensemble received widespread praise at major South Korean award ceremonies, with Roh Yoon-seo earning significant recognition for her breakout performance as a rising young actress.
