“How to Be Thirty” will be a relatable romance centering around the work and love lives of women who have just entered their 30s. The drama follows the story that unfolds when 30-year-old webtoon author Seo Ji Won meets her publisher Lee Seung Yoo, who is also her first love from middle school.

• Jung In-sun
• Hani
• Cha Min-jee
• Kang Min-hyuk
• Song Jae-rim
• Baek Sung-chul
• Lee Chae-won
• Kim Ji-sung