First off, spoiler alert on everything. I'll discuss quite a few things below the picture.
You've been warned.
So the episode starts off with a flash back to Barry's mother's murder. Then, we jump over to Earth-2, many years before. The focus is on a young boy who hears his parents arguing. The boy goes down to see his father who has returned from the army beating his mother. He tells his son, "You have to watch this," and proceeds to place his metal helmet on his sons head and shoot the mother. Skip ahead to the orphanage, and we find out it is Hunter Zolomon, aka Zoom.
Fast forward and jump back into the Earth-1 dimension and Barry is running faster than ever with the new tachyon device and decides he is ready to face Zoom. With the help of Cisco, they are able to open the breaches by controlling Cisco's vibing powers with the goggles from Reverb.
Meanwhile, Wally and Joe are getting closer as father and son. Wally moves into the West household to live with Barry and Joe. Iris also admits that she may have feelings for Barry. So things are starting to look up into more positive light for the West family.
However, in the midst of all the excitement, Harrison Wells finds out that Jay's doppleganger on Earth-1 was Hunter Zolomon, the true identity of Jay/Zoom. Harrison briefs the team that Hunter Zolomon went on to become a serial killer and murder 23 people and be put in an asylum and undergo shock therapy. The particle accelerator accident occurred on Earth-2 and Zoom was born.
Using Zoom's parents pictures against him, Barry, with the aid of the tachyon device, defeats Zoom and locks him in place and interrogates him. Zoom says he doesn't care who he has to kill, so long as he can live. He then says the line we saw in the promo:
You can't... lock up... the darkness.
Then breaks free and goes and kidnaps Wally. Barry decides the only way to rescue Wally is to hand over his speed. Zoom and Team Flash come face to face and Wally is released. Zoom and Team Flash talk as Harrison prepares the necessary means and the team finds out that Zoom does have feelings for Caitlin and that the Man in the Iron Mask's identity is, "someone you wouldn't even believe if I told you," according to Zoom. So Barry runs on the treadmill while Harrison drains his speed as he did before, although completely this time. Barry is human and Zoom flees with the speed and Caitlin!
THEN THE EPISODE JUST ENDS WHILE EVERYONE IS IN SHOCK.
So there you have it, a short summary of Episode 18 of Flash.
It was a good episode, I especially enjoyed the origins of Zoom, even if it was very dark. We were able to see his character develop and what motivated him. However, I am still curious as to what Zoom's "darkness" is - speed force or some other power? He seemingly draws upon even while he is linked to the ground, defeated. Overall, Teddy Sears played the part great in this episode.
The West's on the other hand... they were okay. Iris made one mention of having feelings for Barry and then it just dropped. Wally has the most potential, as he now knows that Iris and Joe work with the Flash. Wally also will be around more because he is living in the same house, so hopefully he will play a larger role in the coming episodes. And Joe was simply Joe, the same character that I have loved all season.
Caitlin and Cisco were both interesting in this episode as well. They both had an internal struggle. Caitlin had to face Zoom, whom she also had feeling before she found out he was who he was. And Cisco had some troubles coming to terms with his Force powers. He did not want to go down the same path as Anakin Skywalker (Reverb) and become Darth Vader. Luckily, Cisco was able to use his powers for the Light Side and open the breaches.
Now to Barry. He made the sacrifice tonight by giving up his speed. He was faster than ever before and loving it, came up with the plan to stop Zoom, and convinced everyone they could do it. Grant Gustin was amazing in this episode, and the coming episodes will be interesting since he has no access to the Speed Force.
Overall, I would give the episode a 8.5/10. I loved it, it wasn't perfect, but one of my favorites this season. I really enjoy Zoom as a villain, although I was worried they would just copy season 1.
Sound off in the comments about this episode! Also, leave some theories about who is the man in the iron mask? My gut still says it's Henry Allen, but who knows... we won't believe if Zoom told us.