Serving as the first television series from Signal producer Lee Jae-moon's company Hidden Sequence, it aired on OCN from August 5 to September 24, 2017 for 16 episodes.

This drama series is based on the popular Daum webcomic Out of the World (세상 밖으로) by Jo Geum-san.

The cult disguises itself as a peaceful church but dark secrets, torture, violence and murder lurk underneath; with even mischievously darker intentions that deceive their most devoted followers.

Three years later, her classmate Han Sang-hwan, the son of the county chief who is now a law student, and his two friends Jung-hoon and Man-hee have a chance encounter with Sang-mi.

He is joined by his third friend and convicted criminal Dong-chul, and both Jung-hoon and Man-hee in his mission, unaware that the cult is just the tip of the iceberg.