Caitlin is determined to save Ronnie, while Barry and the Team have other plans. Meanwhile in Coast City, Tinya is angry at Iris for unintentionally vaporizing her mom.
Tropes:
- Alone with the Psycho: Caitlin with Deathstorm at the end.
- The Bad Guy Wins: While not directly stated, it's implied Deathstorm's trickery of Caitlin (and by extension Frost) throughout the episode was to get the splicer attached to him and make him even more powerful and dangerous than before, which he succeeds at doing.
- Black Eyes of Evil: "Ronnie"'s eyes appear this way at the end, just before Deathstorm reveals his true form.
- The Bus Came Back: Robbie Amell returns in this episode. Ronnie Raymond... not so much.
- Call-Back:
- Both of Ronnie's deaths are shown in flashbacks.
- The team uses one of Eva McCulloch's R-CEM chips for the splicer they build for Ronnie.
- Came Back Wrong: Ronnie did die stopping the singularity, but when he did, something took over his body, transforming him into Deathstorm.
- Cliffhanger: Iris is seemingly vaporized, with a distraught Sue telling Barry about it, and Deathstorm appears before Caitlin.
- Didn't Think This Through: Allegra points out that Chester just sharing all of his scientific achievements via Livestream could be extremely dangerous, particularly in this specific case, when he is talking about technology that could possibly raise the dead.
- "Eureka!" Moment: When Frost says that they will find Ronnie "day or night, rain or snow", Caitlin is reminded of them being trapped in the snow the day she and Ronnie proposed to each other, realizing that this is where she will find him.
- Flaming Skulls: Deathstorm's ethereal form has somewhat resembled this for the last few episodes, and his humanoid form seen at the end looks exactly like this.
- Flashback: Several of them to Caitlin and Ronnie. From them first meeting to proposing to each other and marrying, until the tragic end.
- Foreshadowing: As mentioned in Mythology Gag below, Allegra mentions how her grandmother called death the "Blackest Night", which is the DC story where Deathstorm is prominent, foreshadowing The Reveal at the episode's end.
- Ghost Story: What a bunch of campers tell to each other before the Black Flame appears before them.
- Humanoid Abomination: Deathstorm's true form, which can best be described as "a muscular demon with a skeleton for a head, wearing a mockery of Firestorm's armor, lit on blue fire".
- Ignored Expert: Barry points out how Ronnie's sudden return is Too Good to Be True and Cecile tells Caitlin that he begged her to end his suffering. Yet Caitlin is still determined to save him. Turns out at the end, that she did the wrong thing.
- Immediate Sequel: The Coast City portion of the episode picks up right after Iris unintentionally vaporized Tinya's mom.
- Internal Reveal:
- Caitlin tells the team about Ronnie speaking to her.
- She also tells Marcus about her affiliation with Team Flash.
- Kill the Lights: What Deathstorm does when he is alone with Caitlin.
- Let Me Get This Straight...: Marcus's reaction when he hears about Caitlin working with Team Flash and her dead husband coming back to life.
- Love at First Sight: Caitlin and Ronnie immediately fall for each other in the flashbacks.
- Mercy Kill: What the rest of Team Flash wants to do with Ronnie, after they are convinced that he is in incredible agony. Caitlin objects.
- Mythology Gag: Allegra refers to death as the "Blackest Night", which is the story from which Deathstorm originates.
- Nice Job Breaking It, Hero: Deathstorm manipulates Caitlin (and by extension Frost) into saving him and even destroying the sole device that is able to trap and neutralize him.
- One True Love: Ronnie is this for Caitlin, still. To the point that she immediately calls things off with Marcus (though also to protect him).
- Properly Paranoid: Barry is suspicious about Ronnie suddenly calling out to Caitlin given the events of the last few episodes, and thinks the entire situation is too good to be true. While Caitlin tries to call him hypocritical for be willing to go to hell and back if Iris was in the same situation, he turns out to be right: the entity was possessing Ronnie's body, and Caitlin's actions wound up powering it up to even deadlier levels.
- The Reveal:
- All the victims of the Black Flame were connected to Caitlin, as it was trying to find her.
- The Black Flame isn't actually Ronnie himself, but a mysterious malevolent entity that took over his body following his death in the singularity, and calls itself Deathstorm.
- Sensory Overload: Cecile is in incredible pain when Ronnie tries to connect with her.
- Shout-Out:
- Marcus quotes Plato when parting ways with Caitlin.
- In the flashbacks, Ronnie mentions him and Cisco playing Call of Duty.
- Caitlin also mentions that Ronnie used to play Dungeons & Dragons, much to Chester's delight.
- Swapped Roles: For once, Caitlin is stubborn and determined, while Frost tries to be the reasonable one.
- Thicker Than Water: Despite being worried about her, Frost sides with Caitlin over the rest of the team, stealing the splicer for her, as they are sisters.
- Too Good to Be True: Barry suspects this about Ronnie just coming back to life 7 years later. Sadly, he's proven right in the end.
- Truer to the Text: This version of Deathstorm is much closer to how he was portrayed in the comics, compared with the evil Earth-2 Ronnie Raymond calling himself "Deathstorm" all the way back in season 2.
- Wham Line: "I'm not Ronnie."
- What the Hell, Hero?: Caitlin calls out Barry on his hesitation, pointing out that if he were in this situation with Iris, he'd move heaven and earth just for the slightest chance to save her.
- You Killed My Father: Gender inversion. Tinya is understandibly very angry with Iris over vaporizing her mom, unwillingly or not. It leads to her attacking Iris and seemingly vaporizing her as payback.
