Upcoming SBS drama Startling by Each Step: Ryo might be a fantasy, but the all star cast is very real.

K-pop idols IU (Lee Ji Eun), Byun Baekhyun of EXO, and Girls' Generation member Seohyun (Seo Ju Hyun) have been selected to star in the upcoming fseries alongside actor Lee Joon Gi.

Producers of the show this week confirmed the full cast for Startling by Each Step: Ryo (also known as Moon Lovers), which is based off the Chinese novel "Bu Bu Jing Xin" by Tong Hua. The story was previously adapted for the screen in 2011 by the Chinese network HBS as "Scarlet Heart."

The new fantasy drama adaptationwill be directed by Kim Kyu Tae, who is known for hit Korean dramas such as That Winter, the Wind Blows, It’s Okay, That’s Love, and Iris.

Kang Ha Neul, Hong Jong Hyun, Nam Joo Hyuk, Ji Soo, and Kang Han Na will also appear in the drama.

Startling by Each Step: Ryo marks the TV acting debut for EXO member Baekhyun, while his SM Entertainment label mate Seohyun continues to further her acting career after making her debut in the 2013 SBS drama Passionate Love.

The first script reading is scheduled for Jan. 8.