Who Killed Bryce Walker On '13 Reasons Why'? Suspect Revealed!

Alex is the killer!

In the final episode of the season, it shows Alex (Miles Heizer) and Jessica (Alisha Boe) going up to an injured Bryce on the pier. He gave Jessica the tape that had his confession and an apology on it. While Jessica walked away, Alex stayed behind and said, “You’ve hurt everyone I’ve ever loved.” He then moved towards Bryce and started to push him off the dock and into the water.