Signal

Hae-young realizes the possibility that his brother could have been murdered after learning from Hye-seung that Sun-woo was not guilty.

All Episodes - Season 1

Episode 1

You're Doomed

Episode 2

We Still Have a Chance

Episode 3

We Can Prevent the Killings

Episode 4

We Found the Killer

Episode 5

Changing the Past Alters the Present

Episode 6

Catch Him by All Means

Episode 7

We Must Dig Deeper

Episode 8

How Are You Alive?

Episode 9

Hongwon Dong Case

Episode 10

Someone Has to Stop the Bad Guys

Episode 11

The One Last Case

Episode 12

The Case Was Manipulated

Episode 13

The Real Assailant

Episode 14

Not Now, But Maybe In The Past

Episode 15

Is It Really You?

Episode 16

If You Don't Give Up