After learning that Jay Garrick is Zoom through Cisqo’s vibrations, Barry sets out to re-open the breaches back to Earth-2 to confront and defeat Zoom while he became faster through the tachyon device. Notice that he disappeared briefly before returning back and this is when he was in Supergirl’s Earth in their crossover. I guess we got our answer that Supergirl isn’t going to be touched on in the Flash, but the crossover wasn’t being alluded to again either in Supergirl.
Not everyone is aboard such as Harrison Wells as he doesn’t want to go back to Earth-2, but he learns through Joe that once Barry’s mind is on something you can’t talk him out of it. So he reluctantly helps Barry re-open the breach as Barry tries to get Cisqo to use his powers the same way his Earth-2 counterpart, Reverb, did his. The highlight of this was seeing the super-speed fight between Flash and Zoom that had Flash finally winning and he had him where he wanted until Zoom turn the tables on him by kidnapping Wally West.
A trade is that Barry saves Wally in return to gain all of his speed, but as predictable Zoom uses this to terrorize Earth-1 by kidnapping just about everyone while Barry is helpless. In terms of the 3 act storyline, this is likely the lowest point for Barry for the second season. There was one problem with all this – it all could have been prevented and they’ve written Barry is gullible since the start of the series. He was actually written better in Supergirl and that is saying something here.
The bulk of the episode is the origin of how Hunter Zolomon became Zoom and how he deceived others as Jay Garrick. I’m betting that the man in the iron mask is the real Jay Garrick more than ever. A good episode at best, not great and not bad either.