The Flash season 2's previous episode already revealed that Jay Garrick is Zoom but Barry Allen and his team are oblivious to the big news and still believe that Jay Garrick died a hero trying to take down Zoom.
In an interview, Grant Gustin spoke about Zoom's identity and shared that Barry will not handle the truth about Zoom being Hunter Zolomon aka Jay Garrick very well. Gustin told Entertainment Weekly: "It's betrayal and disappointment in himself. Because it's almost like he's been through this before, and he can't believe he let himself go through it again."
Although fans are confused about how this whole thing will play out, Garrick, who arrived on Earth-1 with no powers, could travel back and forth between multiple universes or even stab himself in the chest by the end of episode 14.
Executive producer Andrew Kreisberg said everything will be explained when Flash season 2 returns from a brief hiatus. Kreisberg told EW: "How all of that plays out and what's actually happening, we'll leave for after the break. But we wanted to go out on this run of episodes with a big reveal, just the same way we did at the end of episode 9 in season 1, where we revealed that Harrison Wells was the man in the yellow suit. Zoom's identity is finally revealed."
In season 1, Eobard Thawne used Wells's identity and mentored Barry to become the Flash, while all he wanted was to use Flash's speed to go back to his home. Now Garrick, who came to Star Labs team as the Earth-2 speedster, used Barry for his own evil plan. Basically, history is repeating itself.
According to Kreisberg, Garrick's betrayal will be even bigger than Eobard. "It's an even larger betrayal than last year in some ways, because they're all going to feel like they should've been inoculated against it. Fool me once, shame on you, fool me twice, shame on me."