Jang graduated from the College of Fine Arts at Seoul National University and attended the Korea Film Academy. Hoping to become a film director, he wrote a screenplay that later became The Mystery of the Cube which went on to win the grand prize at the 1996 Korea Film Promotion Corporation’s screenplay contest. The story later was adapted into a movie and a novel. Since then, he went on to publish such tightly knit, extensively researched fiction as Fate Calculation Clock and The God’s Calendar, while also carving out a bigger role for himself through entertaining, intellectually stimulating, and heartwarming writing. After a brief pause, he published The Ultimate Child in 2013 to phenomenal response from the world of Korean genre fiction and marking his second phase as an author. The Ultimate Child won the grand prize at the 2011 KOCCA Korea Story Contest and was praised as the year’s best Korean mystery by readers. With the 2014 publication of The Puppet, The Immortal Doll, he solidified his status as an author who is hotly sought after both at home and abroad.