Tonight on "The Flash," Cisco, Harry, Earth-2 Barry and Iris had to find Zoom's lair so they could rescue both Earth-1 Barry and Harry's daughter, Jesse Quick. The journey to his hideout was perilous, and the team looked for help from an unusual ally. Back on Earth-1, Joe, Iris, Caitlin and Jay had to find a way to defeat the metahuman Geomancer, who was continuing to terrorize Central City in the absence of The Flash. While it was fun to see the Earth-2 characters again, the biggest reveal, or tease of a reveal had to do with Jay Garrick. "The Flash" has been seeding certain things about Jay's identity over the course of this season -- the loss of his speed, his addiction to Velocity 6, the name of his Earth-1 doppelganger, Hunter Zolomon -- and tonight's episode may have opened the door for a new Jay Garrick theory. This episode also kept all the characters on edge, and pulled a surprise character death that no one saw coming.

Last week on "The Flash" Barry (Grant Gustin), Cisco (Carlos Valdes), and Harry (Tom Cavanagh) traveled to Earth-2 on a quest to rescue Jesse (Violett Beane). While there, they encountered the Earth-2 versions of Joe (Jesse L. Martin), Iris (Candice Patton), Barry, Caitlin (Danielle Panabaker), Ronnie (Robbie Amell,) and Cisco. While Barry, Iris and Joe had very similar lives to Earth-1, Caitlin, Ronnie and Cisco had become villainious metahumans who were working for Zoom. At the end of the episode, Earth-2 Joe was dead, Ronnie/Deathstorm and Cisco/Reverb were dead, and Caitlin/Killer Frost was the only metahuman left alive. Zoom then captured Earth-1 Barry and put him in a glass cage with Jesse and a mysterious man in a metal mask. Back on Earth-1, Caitlin and Jay (Teddy Sears) had been fighting Geomancer, working on stabilizing the breach, and testing a new Velocity serum to help boost Jay's speed. The episode ended in a cliffhanger, with a disabled speed cannon and a captured Barry Allen.

The two-part episode resumed tonight in "Escape from Earth-2," and unmasked some startling revelations. First, in order for Harry and Cisco to track down Barry to Zoom's lair, they needed the help of an excellent hacker, Earth-2 Barry, a fierce police woman, Earth-2 Iris, and an icy metahuman who has been there before, Killer Frost. Killer Frost was reluctant to help, for fear that Zoom would kill her if she led them to his lair, but she decided to help after Cisco and Iris got the drop on her. She led the team to Zoom's hideout, which was a huge cave high up in the mountains. Thankfully Killer Frost was a lot like Disney's Queen Elsa (nice shoutout Cisco) and she was able to build ice-stairs up to the top. While this journey was dangerous, Earth-2 Barry decided to accompany his wife and his new friends in order to save his Earth-1 counterpart. Grant Gustin must have had a lot of fun playing a different, more skittish and geeky version of Barry in this episode. He and Candice Patton had some great scenes together which further strengthened the bond of those two characters. This band of unconventional Earth-1/Earth-2 allies did make it to Zoom's lair, but not before Barry and Jesse made some startling discoveries about Zoom and the man in the iron mask who was being held with them.

The man in the iron mask -- while he was seen just briefly at the end of last week's episode, he didn't look like an easter egg character -- he didn't have any symbols on his body or in his cell that would signal who he was underneath the mask. In tonight's episode, he sat in his glass cell tapping out some kind of code. At first Barry through it was a signal, but Jesse, as tired and hurt as she was, thought it was nonsense. When Barry reminded her of her father's words, that the only person in the world smarter than him, was her, hope was restored a bit, and she conceded that perhaps it was a code. Turns out it was a "Tap Code" that P.O.W.s used in World War II. The code spelled out three letters: J-A-Y. When Barry asked if that meant Jay Garrick, he shook his head yes. When Barry tried to comfort the man by telling him that Jay was safe on Earth-1, the man freaked out and rapidly started shaking his head. Was the man asking about Jay Garrick, or was he trying to spell his own name? Is the man in the mask the real Earth-2 Jay Garrick? If Zoom was trying to harness speed from speedsters, it would make sense that he would be collecting different versions of The Flash. If that is Jay Garrick, then who is the man posing as Jay on Earth-1? So far there are two people he could be.

He could be either be Edward Clariss/The Rival, Jay Garrick's comic book adversary from Earth-2 who attempted to recreate Jay's speed through a serum called Velocity 9 -- sound familiar? He could also be the Earth-2 version of Hunter Zolomon. A few episodes back Jay showed Caitlin the Earth-1 version of himself, a man named Hunter Zolomon. In the comics, Zolomon was Wally West's greatest adversary, his Zoom. If this Garrick is really Clariss or Zolomon, what does Jay look like under the mask? Is that actor Teddy Sears, or is it someone else? There have been a few Earth-2 flashbacks that showed Teddy Sears as Earth-2's Flash, so maybe this imposter Jay can change his DNA somehow? The scary thing about the idea of a fake Jay Garrick, is that Caitlin was lied to again by a man that she trusted. First Doctor Wells/Eobard Thawne, and now Jay. She even perfected the Velocity serum for him, thus creating a stable Velocity 9. At the end of the episode, Jay was able to stabilize the speed canon, but as he closed it, Zoom pulled him back through to Earth-2. It actually looked like Zoom killed him, because Zoom's hand was through his chest. But was this all part of Zoom's plan? Send in a fake speedster and get Caitlin to create a chemical speed generator? It all seemed a little too convenient that the second Caitlin perfected Velocity 9, Jay was killed or taken away.

While Barry was locked in the glass cage he also learned something else: he learned that speedsters could phase through solid objects. When his friends finally found him in Zoom's lair, they were able to break Jesse free, but they couldn't get Barry out. When Barry said he could try to phase through but was unsure if he would be successful, Earth-2 Barry got to encourage Earth-1 Barry with powerful words of hope and encouragement. They both got to find their inner strength in this episode and Barry was able to phase through. On their way out of Zoom's place Barry wanted to rescue the masked man, but was unable to when Zoom showed up. Zoom thanked Killer Frost for bringing Harry Wells to him, but then she double crossed Zoom by freezing him. The whole team was able to escape, except for Killer Frost and the man in the mask. Even Harry and Jesse decided to leave Earth-2 for good and return with Barry and Cisco to Earth-1. Earth-2 Barry and Iris headed for family in Atlantis, and said goodbye to the team from Earth-1. The team made it through the breach on time and they were able to close it so Zoom could never come through again, but that's when they lost Jay.

With an ending that intense, where does that leave all of the characters? Barry is safe back home, but has to deal with the emotional repercussions of spending the day married to the former love of his life, Iris. Harry and Jesse are now permanently on Earth-1, and while Harry can hide out at S.T.A.R. Labs, Jesse will have to find a way to go to school and make new friends. Maybe she and Wally West (Keiynan Lonsdale) will hit it off, considering they are both the new kids in Central City? Caitlin might be happy to see her friends back, but she just lost the new love in her life. How will Caitlin handle watching someone she loves die again? Iris is happy that Barry is back, but will he tell her about their Earth-2 marriage? Lastly, Cisco is back, and while he still has a heart of gold, he now knows the range of his powers. Will he start pushing himself to become more like Reverb? While everyone got out of Earth-2 safely, no one is the same, and each character is going to have to deal with what happened over there in different ways.

Next week King Shark is back and Diggle (David Ramsey) and Lila (Audrey Marie Anderson) come over from "Arrow." It is sure to be just as thrilling as these Earth-2 episodes, and the episode will get closer to unmaking both Zoom and the man who was left behind in Zoom's glass cell. "When King Shark escapes from an A.R.G.U.S. holding tank, Lila and Diggle travel to Central City to warn The Flash. King Shark shows up at the West house and attacks Joe, Iris, Wally and Barry."

"The Flash" airs Tuesdays on The CW at 8 p.m