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As Barry begins mentoring a new speedster, an old enemy in a new form emerges. Meanwhile, Cecile's powers undergo a shift that may allow her to help Team Flash in a new way, as John Diggle seeks help from an unlikely source regarding his problem.
The Flash comics of Joshua Williamson, Final Crisis (mentions of the Dark Monitor and Bleed) and Blackest Night.
Matt Letscher has a fantastic turn here as the reformed Thawne. He also has fantastic chemistry with Kausar Mohammed, who is equally impressive in the first full episode with the Negative Flash.
The effects work for the speedster fights is some of the best in the show's history.
The way Cecile sees the emotions of other people and projects new emotions on to them is similar to how emotions manifested from the viewpoint of Black Lanterns in Blackest Night.
Reverse-Flash describes the technology powering Diggle's box as Transmatter Technology. In the classic JSA and JLA comics, both teams used transmatter cubes to travel to one another's respective universes.
The Reverse-Flash mentions a place called the Orrery of Worlds. In the Post-Crisis DC Comics universe, this was the name given to the core collective of 52 worlds making up the multiverse following Infinite Crisis.
The Reverse-Flash makes mention of a cosmic odyssey awaiting John Diggle. Cosmic Odyssey was the name of a 1988 mini-series which features a major role for the John Stewart Green Lantern.
The Reverse Flash tells Diggle to "drink of the Bleed" within his box once he opens it a second time. In the Post-Flashpoint DC Comics Universe, the Bleed is the limbo realm between realities.
The Reverse-Flash makes mention of a figure named Mandrakk, whom he says was responsible for putting a piece of the Bleed into the cube. In the comics, Mandrakk was a name given to a being known as the Dark Monitor, who became corrupted and began devouring the Bleed between realities, causing the entire multiverse to decay and fall apart. Mandrakk was the final villain of Final Crisis.
The Reverse-Flash also makes reference to the Source Wall. In the mythology of Jack Kirby'sNew Gods, the Source Wall is the boundary between the multiverse and the source of all divine power. Many beings have become trapped in the Source Wall trying to move beyond it and claim ultimate power.
When Ray Palmer calls STAR Labs to describe the Legends' recent encounter with Eobard Thawne, he makes mention of dealing with a minor infestation of serpent creatures from the Morlaidh dimension. In the DC Comics Universe, Morlaidh was the name of a microscopic city located deep in the Amazon jungle, populated by a tribe of aliens who were stranded on Earth and descended into barbarism. Ray Palmer discovered Morlaidh and became its protector in the Sword of the Atom series.
Something about the lightning Meena generates causes it to interact strangely with the natural lightning Barry generates through the Speed Force. This is later determined, through an analysis of biometrics, to be because of Meena tapping the Negative Speed Force.
Barry says a biokinetic chemical reaction occurred when his natural lightning interacted with Meena's artificial lightning.
The biometric lightning oscillation chamber (or BLOC) uses quantum computing to remotely harness lightning from the Earth's upper atmosphere, transforming it into artificial speed.
Thawne notes that when calculating quantum static in genetic speed, you have to account for the tachyons.
Reverse-Flash describes the box Diggle found as transmatter technology, forged at the Orrery of Worlds, which has the power to travel across realities.
Before Meena goes mad with power, the BLOC oscillation level is set at 52 million joules.
Thawne determines that if The Flash can keep Meena running for 119 seconds, that will burn off the rest of her speed, based on her 40% saturation level.
Meena: My name is Dr. Meena Dhawan, and for the next three minutes and 52 seconds, I'm the fastest woman alive.
(Barry runs into the cell block holding the Reverse-Flash.)
Barry: How are you still here?
Reverse-Flash: Well... I wanna see how this ends.
Barry: Don't screw with me! How did you get your speed back?
Reverse-Flash: I didn't?
Barry: Stop lying! I saw you, five minutes ago, 1,000 miles from here wearing your original face, pretending you didn't remember me. So, who is he? A version of you from your past? Answer me!
Reverse-Flash: I don't know. And I don't care. Don't you get it? You took my speed. There's no other versions of me out there, no other tricks up my sleeve. You took everything from me. So, why don't you just leave me alone?
(Diggle rejects the power of the cube, to Reverse-Flash's annoyance.)
Reverse-Flash: You're not special. You're not someone important. This was your last chance to be someone powerful.
Diggle: But I am someone special. Now I realize. The cube was trying to make me someone else... something else. And it even tricked me into believing that somehow I wanted it, too, but... I don't. Because there is no power in the universe more powerful than the love I have for my family.
(Diggle laughs. It is a rare but rich sound.)
Diggle: But I suppose a man like you wouldn't understand that. Because if it came down to a choice between some cosmic destiny, or... being a father, a husband... There's really no choice at all.
(In flashback, Thawne places Meena into the BLOC to save her.)
Meena: You gave up your dream. Your chance to save the world.
Thawne: You are my world.
(Cut to the present, as a sobbing Thawne begs The Flash for help.)
Thawne: So, please. Even if I was this monster somehow, or in another life, don't hold my sins against her. I am begging you. Save her.
The Flash: The Thawne I know has haunted my life since I was just a kid. He's killed people I care for. He deserves to rot. He could never put someone else's needs before his. I'm sorry. You're not the man I thought you were. You're someone better.
As the episode opens, Barry is training Dr. Meena Dhawan by running through trees in a national park. Her top speed is said to be 300 meters per second.
Meena accidentally throws a lighting bolt at Barry which knocks him off guard. He notes that she learned to generate electricity with her powers much faster than he did.
Cecile makes reference to a new client who likes to pay in cash.
While Cecile is making a deposit, the bank is robbed. As Cecile watches the robbers, she sees their emotions as a colored aura around them and discovers she can change the auras around, taking the red anger of the robber and trading it with the yellow fear of one of his hostages.
Cecile causes another robber to feel uncertain (blue), saying they shouldn't be here and should have become an engineer.
According to Gideon and Chester, Cecile's powers have increased 1,000 fold.
Cecile makes reference to being overwhelmed by her powers during the fight with Blockbuster in 814.
Reference is made to Barry becoming emotionless while connected to an artificial Speed Force in 702. He fears the artificial speed source Meena created could have similar unintended side effects, though her emotions seem fine.
Barry goes to Fast Track Labs to examine the speed source, saying that he was informed of the secret project by "a mutual friend who likes to run fast."
Meena agrees to let Barry look at her technology, recognizing him as the new owner of STAR Labs.
Barry says Fast Track Labs is decades ahead of any other lab.
Meena says she understands the physics behind the BLOC just fine, but that her colleague is more familiar with the nuts and bolts of super speed theory. This partner is revealed to be Eobard Thawne, in his original appearance before taking on the appearance of Dr. Harrison Wells.
Thawne introduces himself as the Chief of Engineering at Fast Track Labs and says he's been working there for a year. He is also the only employee who knows about the artificial speed source.
Thawne claims to suffer from a rare form of retrograde amnesia and that he cannot remember anything about his personal life from before one year earlier. Despite this, he still has an amazing knowledge of advanced physics relating to superspeed, which was why Meena hired him despite the worst resume she'd ever seen after he solved an equation that had baffled her for months in seconds.
Barry accuses Thawne of being the Reverse-Flash and being up to something, which Thawne denies.
Barry confirms that ARGUS hasn't posted any alerts about Thawne escaping.
The depowered Thawne is reading The Count of Monte Cristo when Barry visits him in his cell on Lian Yu. This continues a running gag throughout the Arrowverse. Oliver Queen was shown reading the same book while in prison in Arrow season 7 and Lex Luthor was reading it while imprisoned during Crisis on Infinite Earths.
Reverse-Flash denies knowing anything about the other Eobard Thawne.
Barry theorizes that the new Thawne might be from another timeline, like Flashpoint and makes reference to the time remnant Reverse-Flash he created who went on to fight the Legends in Legends of Tomorrow season 2.
Reverse-Flash identifies the BLOC as the same device he built as part of his Negative Speed Force 200 years in the future to replicate The Flash's powers.
Barry realizes this explains why Meena's powers are erratic and interacting badly with his - she's tapping the Negative Speed Force.
Reverse-Flash claims that he's never heard of Meena, so he supposes she is destined to die because continual use of the Negative Speed Force will alter her personality.
As Barry leaves Reverse-Flash behind, it is revealed that John Diggle has been watching their conversation, having come to talk to Reverse-Flash earlier.
Diggle has not encountered the Reverse-Flash since F108, when he was still pretending to be Harrison Wells and that he needed a wheelchair.
Diggle describes his journey since the events of A810, trying to open the box that crashed to Earth near him. This is said to have happened two years ago.
Diggle references his appearances in F716, B309 and S612, consulting with his scientist friends on what to do with the box.
Having run out of options among his scientist friends, Diggle thought to check with Reverse-Flash, who might have knowledge of the device being from the 23rd century.
Thawne asks why Diggle didn't have Lyla interview him and deduces that Diggle is on the outs with his wife. Diggle says he's been spending a lot of time away from his family trying to solve the riddle of the box and that he feels compelled to open it again.
Reverse-Flash agrees to help Diggle open the box, in exchange for being allowed to look inside once it is open.
Barry is convinced that the new Thawne is from the Flashpoint reality, though he has no idea how he survived his apparent death at the hands of the Black Flash in L217.
The Flash shows up at Fast Track labs and accuses Thawne of trying to infect Meena with more and more Negative Speed Force Energy.
Meena attacks The Flash and runs off, saying she needs more speed.
Meena begins draining power from the power lines on a remote country road.
Thawne says that cubes like the one Diggle found appear to people with the potential to change the destiny of reality at a turning point in their lives. He claims the box closed because Diggle was not ready to accept the power it offered then.
Under Thawne's direction, Diggle is able to open the box again. However, he throws it away, rejecting it and it vanishes.
Diggle claims to have seen 1000 lives he might have lived, but all of them required him leaving his family. He didn't think it was worth the price.
Diggle leaves the Reverse-Flash behind and calls his wife, Lyla, to tell her he is coming home.
Meena's lightning shorted out Barry's powers and the radio in his costume.
Thawne reveals that he and Meena fell in love as they worked on the BLOC together, as they both had idealistic dreams of what they could do with the power it offered.
Thawne claims that all he remembered of his past life was that he was meant to be a speedster, apart from visions of the BLOC and an understand of the physics of how to make it work.
Thawne was meant to use the BLOC, since it could only work for one person. However, when Meena suffered a cardiac arrest due to her heart condition, Thawne sacrificed his chance at super speed to save her life.
Barry believes that this Thawne has honestly reformed, based on how he talks about truly loving Meena.
Barry and Thawne figure out that the Negative Speed Force is pushing Meena to absorb electricity from power junctions around the city to keep control of her. This leads her to attack the Keystone Cleveland Dam.
Meena is able to cancel out The Flash's power and is about to kill him when Thawne pleads with Meena to fight the Negative Speed Force. His love manages to bring her back.
The Flash suggests that Meena can continue using the BLOC provided she uses her love for Thawne as a lightning rod, like he does with Iris.
Chester agrees to help tinker with the BLOC, like he did with the STAR Labs artificial speed source.
Ray Palmer calls Chester and relates the events of Legends of Tomorrow Season 7 to him, discussing how he met with Dr. Nate Heywood for drinks and learned that the Legends encountered Thawne and witnessed his death in L711. Ray suggests that maybe the Time Wraiths resurrected Thawne and put him in the present day as a reward for his heroic actions.
Cecile goes out on patrol and prevents a mugging by giving a man nausea, like The Top. Unbeknownst to Cecile, however, she is being watched by The Top.
Chillblaine calls Caitlin and tells her that he figured out a way to bring back Frost without the Mirror Gun she was using.
On Lian Yu, Deon appears to the Reverse-Flash and says he had been looking for him, but couldn't find him until the light from Diggle's cube showed him and some other people where to find him. Deon says it is time for the Reverse-Flash to fulfill his destiny.
John Diggle has spent most of the two years when he wasn't appearing in other Arrowverse series searching for a way to open the box he found in the Arrow series finale.
The Bottom Line
This is the kind of Flash story we used to enjoy quite frequently, with deep dives into the lore of DC Comics and some solid performances from the guest stars.