As Barry helps his daughter, Nora, become a better speedster, he and Team Flash also track down a meta stealing high-tech weapons, only to cross paths with a new foe named Cicada, who is hunting the very same meta with nefarious intent. Meanwhile Caitlin and Ralph try to help Cisco get over Gypsy.
- Barrier Warrior: Vanessa Jansen a.k.a. Block uses force fields to not only block attacks, but to crush people to death with them.
- Blessed with Suck: Due to the connection between his and Gypsy's powers, Cisco literally can't get her out of his head.
- Body Horror: Block kills people by compressing them into literal blocks of meat. Viewers are spared from seeing the messy results, not that it helps much.
- Confess in Confidence: Singh tells Iris that his information on the victim has to be off the record.
- Continuity Nod:
- Caitlin namedrops Ronnie and "Jay" in a conversation about exes.
- Harry's upgraded mental activity dampener reappears.
- Curb-Stomp Battle:
- The Dreaded: Cicada to Nora, if her Oh, Crap! expression is anything to go by, and it looks like he will be this to the rest of Team Flash as well.
- Eager Rookie: Nora is way too eager to impress her dad, trying to pull off the tricks Barry does without properly mastering the speed to execute them. After having a heart-to-heart with Joe where Barry realizes Nora wants to impress him — her hero whom she puts on a pedestal — Barry decides to show her a montage of all the times he lost control during training.
- The Faceless: Averted, since we, as the audience, actually do see Cicada unmasked. Since he's a new character, it doesn't reveal anything about him.
- Fandom-Enraging Misconception: Invoked at one point, in order to snap Cisco out of his zoning out, Ralph states "Han shot second", even taking the moment to apologize after it works when Cisco grabs him in a rage.
- Fish out of Temporal Water: On her first day masquerading as a present day CSI Intern, Nora forgets to consider that a future gadget for keeping evidence uncontaminated has not been invented yet.Nora: Sorry, you mean you don't have a scene wide modified personic frequency field, to avoid cross contamination?Barry: I don't even think we have some of those words yet!
- Hidden Depths: Both Caitlin and Cisco are extremely surprised about Ralph's advice on how to get over a breakup. Especially so because it is the 27th advice of a list with far more useless stuff before that.
- Important Haircut: Averted. Ralph's stylist attempts to cut Cisco's hair, but he reacts very negatively to the idea. The stylist just ends up just brushing it back.
- In the Back: How Cicada hurts Block.
- Keeping Secrets Sucks: Refreshingly averted. The episode opens with Nora and Barry filling in the rest of Team Flash about Barry's future disappearance and how Nora was faking negative tachyons to see her dad and change the future.
- Knight of Cerebus: Any and every scene regarding Cicada is very dark.
- Loving a Shadow: A parent-child variant; Nora grew up idolizing the Flash as a perfect hero, but doesn't know anything about Barry Allen. Barry decides to rectify this by showing her how he messed up during the first years with superspeed.
- Mood Whiplash: Barry, Nora, Cisco, and Ralph are jubilant after apprehending Block, only for the mood to become very serious when Cicada tries to make an attempt on her life...as well as theirs.
- Never Hurt an Innocent: Well, he did put them into a hospital, but Cicada did indeed refrain from killing the cops guarding Gridlock.
- No-Nonsense Nemesis: Cicada doesn't bother with an Evil Plan, a Motive Rant, or even telling the heroes who he is. Instead he just walks up to them and starts handing them their asses.
- Oh, Crap!: Nora when she recognizes the name Cicada.
- Pet the Dog: Possibly, as Cicada refrains from killing Barry when he hears Nora calling out to her father in shock.
- Power High: Cecile shows a pretty unhealthy obsession about her telepathy once more, when it seems like it's fading again. In the end, she seems to have gotten over it.
- Power Incontinence: Cecile's powers are fading even more, to the point that she's lost them.
- Power Nullifier: Cicada's knife acts as this, rendering Barry, Cisco and Ralph powerless when they confront him.
- The Reveal: Who faked the death certificate of Caitlin's dad? Her mom!
- Screw Destiny: Iris isn't impressed by the headline detailing Barry never came back from his disappearance, noting how Team Flash has changed the future before.
- Serious Business: Cisco's locks. He threatens a barber who even dares to cut his.
- Shirtless Scene: Cicada is shirtless after taking off his equipment. Some wounds can be seen on his body.
- Shout-Out:
- Ralph quotes "Negative Ghost Rider" from Top Gun (1986).
- Cisco compares Cicada's telepathic control over his dagger to The Mighty Thor's Mjolnir.
- Sickening "Crunch!": During Block's first kill, there is a really nasty version of this when she reduces him to a literal block of flesh.
- Stable Time Loop: Similar to the previous season's finale, Nora prevents Cicada from killing her father, a few years before she is born.
- Swiss-Cheese Security: Right after Detective Singh is introduced to Barry's "new intern" Nora, Iris walks onto an active crime scene with zero resistance. Singh immediately asks someone to secure the scene, in a tone that suggests that he's wondering why no one was doing that in the first place.
- Unwanted Assistance: Cisco is not particularly eager to receive help from Caitlin, and especially Ralph, to get over Cynthia.
- Wham Shot: Caitlin sees in Cisco's vibe who forged her father's death certificate: Dr. Tannhauser, her mother.
