Ku Hye-sun entered the entertainment industry after gaining popularity on the internet as an ulzzang. She began her acting career in one-act dramas and the sitcom Nonstop 5. Ku soon rose to fame in the drama Pure in Heart and surprised critics with her performance in the historical drama The King and I.[1] She is most well known for portraying Geum Jan-di in the mega hit KBS2 drama Boys Over Flowers opposite Lee Min Ho.[2] After a year in limbo with no broadcasting slot, her first pre-produced drama The Musical finally aired in September 2011.[3][4]
Ku made her official debut as a director through her short film The Madonna at the 2009 Puchon International Fantastic Film Festival.[5] After writing and directing her first feature-length film Magic in 2010, she continued directing short films such as You and Fragments of Sweet Memories,[6][7][8][9] as well as trailers for film festivals.
On March 11, 2016, Ku was confirmed to be dating her Blood co-star Ahn Jae-hyun since April 2015.[50] Shortly after confirming dating, rumors circulated that the couple were planning to get married by the end of this year. On April 8, 2016, it was confirmed that Ahn and Ku are going to be married on May 21, 2016.[51] They announced that instead of holding a wedding party, they would have a simple meal, and would donate the money to the pediatric ward of Severance Hospital.[52] As of May 20, 2016, Koo Hye Sun and Ahn Jae Hyun were officially married, as Hye Sun was spotted at city hall registering for their marriage licence. The following day the couple has a small dinner with both families in attendance