there is only two dramas that i could really recommend to you (because i only like thriller)
they are masterpieces :
drama :
God's Gift - 14 Days (Soo-Hyun (Lee Bo-Young) travels back in time to bring her dead child back to life)
Mother (Korean Drama) (A young girl named Hye-Na (Heo Yool) is abused by her mother Ja-Young (Ko Sung-Hee). Although she is not okay, she tells other people she is alright. Soo-Jin (Lee Bo-Young) is a temporary teacher at the elementary school where Hye-Na attends. Soo-Jin is aware of her situation and decides to become her mother.)
movie:
Vanishing Time: A Boy Who Returned
Four young kids, including Sung-Min (Lee Hyo-Je) and Soo-Rin (Shin Eun-Soo), take a trip to the mountain together. They plan to sneak into a restricted area to watch a planned explosion.
The next day, Soo-Rin is the only one found. A few days later, Sung-Min (Gang Dong-Won) appears again, but he is not the same 13-year-old boy. Sung-Min is now adult.