Best Signal Episodes, Ranked
All 16 episodes of Signal scored and sorted — from the 9.4/10 high of S1E8 to the 8.8/10 of S1E1.
Our rating: 9.16/10 average across 16 episode reviews (best 9.4, lowest 8.8).
Signal is one of those rare shows where the ratings barely dip — sixteen episodes, all between 8.8 and 9.4, every one of them Season 1. There’s no slump to warn you about. What you get instead is a slow, deliberate climb: the show starts strong and keeps tightening until the final stretch is basically all peak.
The opening pair, S1E1 “A Dead Suspect Opens the Line” (8.8) and S1E2 “The Deadline Passes, Then Time Reopens” (8.8), sit at the bottom only because they’re doing setup work — establishing the walkie-talkie link across decades before the emotional stakes have teeth. They’re good. Everything after is better.
Three episodes share the top at 9.4. S1E8 “The Dead Woman Walks Into the Room” is the first one that fully fuses the cold-case mechanics with the gut-punch of changing the past. S1E13 “Jae-han Comes Home Fifteen Years Too Late” pays off the show’s central absence. And S1E15 “The Past Refuses to Stay Buried” pushes into the home stretch without losing its grip.
The back half almost never drops below 9.3 — S1E9, E10, E12, E14 and the finale all land there. If you’re rationing your time, the first two episodes are the price of admission; from S1E7 onward, Signal doesn’t waste a minute.
| Rank | Ep | Episode | Score |
|---|---|---|---|
| T-1 | S1E8 | The Dead Woman Walks Into the Room | 9.4 |
| T-1 | S1E13 | Jae-han Comes Home Fifteen Years Too Late | 9.4 |
| T-1 | S1E15 | The Past Refuses to Stay Buried | 9.4 |
| T-4 | S1E9 | Hongwon-dong Opens Soo-hyun's Old Wound | 9.3 |
| T-4 | S1E10 | Soo-hyun Finds the Door Again | 9.3 |
| T-4 | S1E12 | Inju Buries Jae-han Twice | 9.3 |
| T-4 | S1E14 | Sun-woo Was Murdered | 9.3 |
| T-4 | S1E16 | The Last Transmission Refuses to Close | 9.3 |
| T-9 | S1E7 | The Blue Diamond Reopens a Dead Woman's Case | 9.2 |
| T-9 | S1E11 | Hongwon-dong Ends, and Inju Opens the Old Wound | 9.2 |
| T-11 | S1E4 | A Father Lies, and Jae-han Pays | 9.0 |
| T-11 | S1E5 | Jae-han Pays for Changing Time | 9.0 |
| T-11 | S1E6 | A Wrongful Arrest Keeps Killing People | 9.0 |
| 14 | S1E3 | The Past Saves One Life and Claims Another | 8.9 |
| T-15 | S1E1 | A Dead Suspect Opens the Line | 8.8 |
| T-15 | S1E2 | The Deadline Passes, Then Time Reopens | 8.8 |
Scores reflect our episode reviews. Tap any episode to read the full review, or browse the whole Signal season recap from the top.