Armed with the knowledge that Savitar is a future version of himself, Barry takes desperate measures to rob Savitar of his knowledge of their future - a decision that leaves Barry with total amnesia! Meanwhile, HR continues to push Tracy Brand to develop a "speed trap" for Savitar and Killer Frost approaches Team Flash with an offer they can't refuse.
The "Mirror, Mirror" episode of Star Trek: The Original Series (mentioned by Cisco, dealt with evil twins) and every stupid sitcom episode where hilarity ensues when the main character gets amnesia.
Even if Cisco's memory machine had worked as intended, how the heck were they supposed to use it to defeat Savitar? Barry wouldn't be able to remember any details of any plan they made!
Couldn't Julian - as Barry's supervisor - step in to take his place in court if Barry was unable to testify due to illness?
Barry's speech at the end - where he talks about needing darkness to define himself - seems to be totally opposed to everything that has ever been said about Barry being a positive, hopeful, light-filled hero in damn near literally every episode of the show before now!
Grant Gustin does triple duty this episode, playing both the normal Barry, Savitar and the "happy" Barry with amnesia.
The sequence of Barry losing control of his speed after kissing Iris is well shot and directed - a great use of the show's special effects budget.
The amnesiac Barry asks to be called Bart. In the DC Comics Universe, Barry Allen's grandson, named in his honor, goes by the name Bart Allen. Bart Allen goes on to become The fourth Flash, after using the codenames Impulse and Kid Flash.
This episode introduces an arsonist called Heat Monger, who was apparently brought to justice by The Flash. In the DC Comics Universe, there was a supervillain called Heatmonger who was part of the Nazi super-villain group known as The Aryan Brigade. Never given a real name in any of the stories she appeared in, Heatmonger was a Caucasian woman with blonde hair and robot arms that fired focused blasts of intense thermal energy.
The DCTVU version of Heat Monger is a man named Lucius Coolidge. He uses a backpack-mounted flamethrower to set things on fire.
Barry suggests that "The Streak" might be a better name for him than The Flash. This is the name that Iris originally used for him on her blog in Season One before Barry told her he called himself The Flash.
Iris says at one point that "happy Barry" seems like the way Barry is supposed to be. In the original DC Comics Universe, before the story The Flash Rebirth mini-series, Barry Allen was a happier, more positive character. This is because - as revealed in The Flash: Rebirth - Barry had an entirely different life before The Reverse Flash went back in time and killed Nora Allen, changing Barry's past to make Barry a more miserable person while still ultimately becoming The Flash.
The device which Julian and Cisco create uses a magnetic disruption to break the chain between the hippocampus (the part of the brain that absorbs new information) and the cortex, where long-term memories are stored.
Julian guesses that Barry's psychogenic retrograde amnesia is due to his and Cisco not accounting for Barry's increased neural velocity.
Tracy Brand is working on an "accelerated matter micro-generator projectile" - a.k.a. The Speed Force Bazooka. This is the device that will trap Savitar in The Speed Force.
The accelerometer of The Speed Force Bazooka sucks up a lot of air watts.
Shellac is a resin secreted by female lac bugs, found in large quantities of the trees in Thailand. Shellac flakes are the accelerant used in all of the arson cases associated with Heat Monger.
Flame temperature and burn patterns are calculated in order to determine the accelerant used to start a fire.When shellac is burned into potassium perchlorate or ammonium perchlorate, it is a tell-tale sign of a high-temperature accelerant fire.
Tracy becomes inspired by HR's mention of sparks and imagines "a modified high-voltage climbing arc" with sparks "jumping between two parallel wires..."
Killer Frost asks for a girard processor, saying that it will help her to prime Barry's neocortical and medial frontal lobes.
The parts for the STAR Labs Particle Accelerator included a synchotron with iridium plating and a dubnium capacitor.
Cisco builds a device that can send electrical charges through the transmitters in Barry's Flash costume, hoping that the shock might jolt his memories. This puts "fuel in the tank", but they still need a visceral memory to "turn the ignition". Iris does this by telling Barry about how his mother died and how she comforted him when the shock finally wore off and he began crying when they were kids.
CODIS is an acronym for Combined DNA Index System.
The Speed Force Bazooka will magnetize Savitar's radial field and keep him in in a state of perpetual stasis. Unfortunately, it requires 3.86 terajoules of energy. This is more power than can be found in the sun.
Savitar: It's like looking in a mirror. (gestures to the scarred side of his face) Well, not quite.
Barry: You're not so scary without your armor.
Savitar: What can I say? I outgrew red.
Barry: I know what you are. You're a time remnant.
Savitar: A temporal duplicate. Created when you run back in time and meet yourself. You brought a remnant to life last year to defeat Zoom. (mock-cheerful) Your duplicate died saving the Multiverse and you continued your happy little life. And it would have stayed that way... but then you decided to play God. You created Flashpoint and changed everything.
Barry: I went to the future. My future self told me that he created time remnants to stop you. That you slaughtered them all!
Savitar: All but one. Me. I lived. But a funny thing happened when I did. You, Joe, Wally, Cisco? You all shunned me because I wasn't the true Barry Allen. (mockingly) I was an aberration. A disposable hero. Future you failed to mention that, didn't he?
Barry: How did you become Savitar?
Savitar: I was broken. And alone. I wanted the pain to end. And that's when I realized the truth, Barry. God feels no pain. All I had to do was become one. And I only needed two more things. (holds up a finger) For Iris to die so that you are driven so far into the dark that I can be born.
Barry: And the other?
Savitar: (smirking) It may sound ironic given who I'm talking to... but I'll keep that one to myself.
Barry: (starting to vibrate his hand at super-speed) What happens if I kill myself? If I die, then you'll never be created.
Savitar: Cause and Effect's a tricky thing. Didn't work so well for Eddie, did it? Shot himself in the chest? Thawne's still kicking around? See, that's the thing about time-travel, Barry. The more you do it, the less the rules apply to you!
Barry: But us having this conversation now - we're changing the future!
Savitar: Are we?
Barry: (To Iris) Jay told me that we're not gods. He was wrong. We could be. Any speedster, and it wouldn't take much. When the love that we feel in our hearts is drowned in anger? When the bad memories outweigh the good ones? What am I going to have to become to stop him?
Cisco: Okay! Ready for zapping!
Joe: Can we not call it zapping?
(Killer Frost enters the room where Savitar is kneeling.)
Killer Frost: What's that saying? "Man plans but then God laughs?" Well, men are planning. And what is The God of Speed doing? Kneeling. Brooding time is over. You revealed yourself. Now what? Any idea what to do with Flash and Friends? Because we are getting pretty close to your big becoming and if we don't take them down, neither one of us gets what we want.
(Killer Frost knocks on Savitar's head.)
Killer Frost: Hello? Anybody home?
(Savitar is suddenly standing, gripping Killer Frost by the throat, choking her as he forces her against the wall.)
Killer Frost: (choking) What are you doing?
Savitar: Who are you?
Killer: Frost: What's wrong with you?!
Savitar: Who... am... I?
Killer Frost: You got rid of Barry's memories. What Barry remembers, Savitar remembers.
Julian: So Savitar's lost his memories too?
Joe: Savitar loses his memory. He doesn't go along with the plan to give Wally powers.
Killer Frost; Cause and effect. But, if you let me help you figure out how to give Barry's memories back, everything goes back to the way it was.
Cisco: Kid Flash runs again...
Iris: And Savitar survives...
Wally: And Iris dies.
Killer Frost: Life is full of difficult choices.
Iris: Or it isn't. If Savitar gets his memory back, what's in it for you?
Killer Frost: That's my business. You think -that- Barry can become The Flash?
Iris: Yeah... he can learn.
Wally: I still know how to do everything. I can teach him.
Killer Frost: Okay. Maybe this is how you defeat Savitar. But there's still a lot of villains in this city and no Flashes to protect it. Is that really a chance you're willing to take?
(HR and Tracy have just kissed.)
Tracy: (as if thinking) Sparks...
HR: You felt them too?
Tracy: No! I mean, yes, obviously, but...
HR: (relieved) Okay.
(Tracy moves past him to her computer.)
Tracy: Sparks! Jumping between two parallel wires....a modified high-voltage climbing arc...
HR: I guess my work here is done...
(Cisco is telling a Julian a story while Killer Frost is working in the same room.)
Cisco: There was this one time we had this very strict deadline, and Dr. Wells was super hard on us. All of us! Even Hartley.
Julian: Who - who is Hartley?
Cisco: Oh, he was this guy we used to work with. Such a dick. You actually reminded me a lot of him when you first came on board. Anyway, so we were working on the iridium plating for the, um... (snaps fingers and looks to Killer Frost) What was it called again?
(Killer Frost ignores him and moves to another work station where she can have her back to Cisco and Julian.)
Cisco: The synchotron. That's what it was. So anyway, we were struggling. And we were burning the midnight oil. And we could not get the dubnium capacitor to hold a single charge. And so all of a sudden, Ronnie just loses all his chill. He turns beet red and he starts yelling at the thing like, "C'mon you dumb-nium capacitor!"
Killer Frost: "... take charge."
Cisco: (pointing at Killer Frost) Yes! Yest! Oh, My God! (sighs) I think about all the memories I cherish most... and you're in every single one of them, Caitlin.
(There is a long pause. When Killer Frost speaks, her voice is noticeably softer. Like Caitlin's was.)
Killer Frost: Let's figure this out. I don't want to be here any longer than I have to.
The Flash: I don't think I can put this fire out alone!
Kid Flash: You don't have to.
(Barry looks over and sees a second lighting bolt moving alongside him.)
Barry: So... how do we know each other?
Wally: Oh, I'm your brother.
(Barry looks down at his hand as if checking the color of his skin.)
Barry: Yes, I am a CIS at the CCPD under the expert direction of Julian Albert. Smiley face.
(Barry blinks as the judge gives him a strange look. Cisco glares at Julian, who is typing the words Barry is reading off of his smart glasses.)
Cisco: You want to cut it out with the emojis?
Barry: Pain and darkness? It's a part of me. You know, I need it to fuel me. To push me to be a better person. To be a better hero. To keep me from ever forgetting who I am.
Iris: Now that is the Barry Allen I know and love.
Savitar reveals that he is a time duplicate made by a future Barry Allen - ironically, the only one who survived being killed by Savitar before he was trapped in The Speed Force. It was his being shunned by Team Flash - who saw and treated him as a disposable aberration - that pushed him over the edge.
Savitar refers to the events of 123 (Eddie Thawne committing suicide to stop Eobard Thawne from ever existing) and 223 (Barry's creation of a time remnant to stop Zoom).
According to Savitar, the rules of time travel apply less and less the more one does it.
Savitar's armor is capable of independent motion - with Savitar either controlling his armor to move telekinetically or the armor having some sort of artificial intelligence that responds to his commands.
Earth 19 has Star Trek, but only the Voyager series.
HR Wells and Tracy Brand both use coffee - a notorious stimulant - to calm themselves down. They both enjoy piping hot Indonesian dark roast with raspberry and coriander.
HR and Tracy kiss.
Barry cannot remember if he is a warm-weather or cold-weather guy.
Barry was in the Science Club, Key Club, Astronomy Club, Yearbook Committee and Anime Club in high school. He was a big fan of Dragonball Z. Iris was not.
Wally loses his speed powers because now Barry never becomes Savitar to give him his speed powers.
Cisco mentions Hartley Rathaway - last seen in 217. He says Julian reminded him of Hartley, at first.
Iris recalls that Barry was in shock when Joe brought him to their house. She held him later that night when he finally started crying. She thinks that was the night they fell in love with each other, though they wouldn't realize it for years.
Barry's mother's maiden name was Thompson.
In third grade, Barry renamed the class hamster to Alexander Ham Bell.
As she is leaving STAR Labs, Killer Frost's eyes momentarily flash back to Caitlin Snow's normal eye color, suggesting that Caitlin is warring to take control of her powers.
In the final scene of the episode, we see King Shark, last seen in 215.
Apparently, The Flash brought The Heat Monger to justice in a previous adventure and Barry was the CSI who handled the evidence on his case.
The Boomerang Factor
The entire episode is dependent on an unrealistic depiction of amnesia and Cisco being a total idiot in order to work.
The Bottom Line
Quite possibly the most profoundly stupid episode of The Flash ever. And yet, despite the amnesia plot being total rubbish and the villain of the weak being a forgettable Heatwave rip-off, there's a lot of good moments here. Unsurprisingly all these moments have nothing to do with the main plot and involve Cisco trying to provoke a feeling in Killer Frost, the sudden romance between HR and Tracy and Iris reveling in an honestly cheerful and happy Barry Allen. If we could have gotten these moments without a hackneyed Amnesia story-line, it might have been worth it.