An anonymous tip leads the police to a hotel pool party; Do Jeong-u cracks the code to learn the location of the fourth murder.

Former FBI profiler Jamie Leighton joins the task force; Lee Ji-uk secretly tails a victim to capture footage and nail an exclusive.

When Son Min-ho is named as the next target, the team is briefed on the White Night Village tragedy; Min-ho suspects a survivor as the culprit.

After Jeong-u reveals he's from White Night Village, Jamie opens up about her dark childhood; the task force keeps a close eye on Min-ho's home.

Jeong-u is put in charge of Min-ho's protection; a news segment about the police officer's heroic rescue helps Jamie piece together key clues.

Gong Hye-won catches the criminal red-handed at the scene, but is perplexed when prosecution takes over the case; Jamie seeks answers about her surgery.