With the wedding just around the corner, Barry finds himself preoccupied after the startling revelation concerning the DeVoes. Due to his obsession, Iris and the others fear Barry may commit a drastic action in an attempt to prevent another crisis akin to their nemesis of the past.
- Alas, Poor Villain: As malevolent and menacing as the Thinker has been built up to be, it's still very hard not to pity him, when DeVoe is revealed to be diagnosed with an evolved form of ALS.
- Amplifier Artifact: DeVoe's thinking cap prototype, like in the comics, otherwise impossible to power but by lightning generated by the particle accelerator explosion.
- Appropriated Appelation: DeVoe likes the name Team Flash fashioned for him, the Thinker, although he admits he found it interesting that there was a possibility they'd choose "the Teacher" instead.
- Ascended Fanboy: In the flashbacks, Thawne mentions that he is a big fan of DeVoe and apparently looks forward to helping create one of the Flash's greatest enemies.
- Batman Gambit: Thinker spends the entire episode playing Barry and Team Flash like a fiddle.
- Bait-and-Switch Comment: Barry asking Cisco to vibe DeVoe through a mug. Cisco complies, and sees that Barry is right, about Marlize' macaroni and cheese.
- Body Horror: At the end, it's revealed DeVoe is merely wearing a wig; underneath is his exposed brain.
- Brick Joke:
- After a lengthy confrontation with the DeVoes at the beginning of the episode, Barry and Joe take their leave, and run into Harry outside; Barry and Joe forgot that their team is still on standby.
- It wasn't until they were finally sure that DeVoe is their guy and figured out what he's capable of that Cisco comes up with his supervillain moniker.
- The Bus Came Back: Wally returns at the end of the episode.
- Blessed with Suck: The particle accelerator and the thinking cap increased his intellect exponentially, however the energy in his nervous system is being funneled to his brain, thus consecutively shutting down parts and functions of his body, slowly killing him.
- The Cameo:
- Barry showing DeVoe pictures of the bus metas currently accounted for: Deacon, Sharpe, Dibny and Chayton. Devoe feigns unfamiliarity with all of them except Clayton, who worked at the same university previously.
- Eobard Thawne (in his disguise as "Harrison Wells") in the flashbacks.
- Cassandra Truth: All of Barry's intuitions about Clifford DeVoe throughout the episode are absolutely correct, despite no one else believing him. It's only at the end after Clifford willingly confesses to Barry that he's vindicated.
- Complete-the-Quote Title: On the famous French philosopher's René Descartes proposition "I think, therefore I am," indicating DeVoe, commonly known as "the Thinker" in the source material.
- Continuity Nod
- DeVoe and his wife were there during the press conference for the particle accelerator, but they only made their presence known after Barry and Iris chase a purse snatcher who took the latter's belongings.
- The episode reminds us that the Particle Accelerator blew up during a storm because, like Barry, DeVoe was struck by lightning.
- DeVoe mentions Grodd, but not by name.
- Cisco believes that Barry being paranoid about DeVoe is because of the wheelchair bit, and then points to Harry, to the latter's chagrin.
- Continuity Snarl: Previous episodes of the show, as well as Arrow, state the particle accelerator explosion happened in December 2013. Now in this episode, it apparently happened on January 7th of that year.
- Dark Lord on Life Support: DeVoe's hover chair is keeping him alive.
- Ditzy Genius: Before becoming the Thinker, Clifford was already very smart, but incredibly clumsy, he even had problems deciphering his own notes.
- Even Evil Has Loved Ones: Clifford and Marlize DeVoe's descent into villainy has done nothing to diminish their love for each other.
- Flashback B-Plot: While Barry tries to prove DeVoe is not who he seems in the present, flashbacks show us us DeVoe's origins on the night of the accelerator explosion and the aftermath.
- Foreshadowing:
- Clifford was a perfectly normal person, that is until four years ago. This sets up the revelation a little later in the episode that he's also a victim of Thawne's machinations.
- In the flashbacks, Thawne speaks of the things to come while looking at Barry and also recognizes DeVoe by name.
- From Nobody to Nightmare: DeVoe used to just be another meek history professor in college. Then the particle accelerator explosion granted him limitless knowledge.
- Idiot Ball:
- Barry discovers DeVoe has a camera in the lab...and is then somehow surprised that DeVoe knows he's the Flash. That also might explain how DeVoe knows the name "Thawne".
- It never occurs to him that the camera started beeping as bait.
- He also thinks it is a smart idea to break into his house without any facial concealment, and searches it at normal speed.
- Barry discovers DeVoe has a camera in the lab...and is then somehow surprised that DeVoe knows he's the Flash. That also might explain how DeVoe knows the name "Thawne".
- I Know You Know I Know: There's a bunch of this between DeVoe and Barry. Essentially, Barry knows that DeVoe is the Big Bad and thinks he can catch him off-guard, but DeVoe is well aware that Barry has discovered his identity. Likewise, DeVoe reveals that he knows Barry's Secret Identity, which Barry somewhat suspected because he knows DeVoe was spying on Star Labs.
- Insistent Terminology: When Barry adresses Clifford as Mister DeVoe, Marlize insists its Professor.
- Internal Reveal
- Barry finds out that DeVoe's Samuroid is his means of keeping an eye on S.T.A.R. Labs.
- Barry (and the team when he told them) learns that DeVoe knows his Secret Identity.
- Leaning on the Fourth Wall: DeVoe telling Barry that he's not good at keeping his identity a secret, one of the common complaints in the earlier seasons.
- Meaningful Echo: Iris once again assures an anxious Barry that they can face whatever life, DeVoe or any other villain will throw at them, as long as they do so together, instilling to him she isn't afraid as "[they] are the Flash."
- Motive Rant: DeVoe almost tips his hand in his civilian persona by starting one about not just teaching people, but changing how they think so they can learn better, but his wife stops him before he really gets into megalomania. It's still menacing, for the audience, knowing what he's capable of.
- No Good Deed Goes Unpunished: In the flashbacks, Clifford laments how many people are using their powers for committing crimes and wreaking havoc, while he wanted to help the world and got a terminal disease for it.
- Non-Action Big Bad: DeVoe, at least in this episode. In fact there's no fighting at all in the episode since it mostly focuses on DeVoe's origin story and Barry's (unsuccessful) attempts to prove he's a villain. The episode's climax ends up being a conversation with the villain rather than a fight.
- Noodle Incident: Wally mentions fighting a giant starfish from outer space (presumably Starro) while on his sabbatical.
- Offscreen Moment of Awesome: Wally taking on Starro the Conquerer during his time away from S.T.A.R. Labs.
- Omniglot: Clifford is fluent in several languages, most notably japanese.
- Pet the Dog: DeVoe makes it clear he doesn't intend to interfere with Barry and Iris' wedding, since he respects The Power of Love too much.
- Plausible Deniability: While playing the innocent, DeVoe notes that he doesn’t know any of the currently identified victims, other than Mina Chayton, who was his former co-worker.
- Power at a Price: DeVoe's enhanced brainpower is at the cost of strength being drawn from the nerves elsewhere in his body, starting with the loss of ability to walk; in fact he's dying from what is comparable to an accelerated case of ALS.
- Properly Paranoid: In the end, Barry's suspicions are proven to be true, against the judgement of the whole team, no less.
- The Reveal:
- DeVoe's thinking cap was powered by the Particle Accelerator explosion and also left him a cripple.
- DeVoe's hover chair keeps his body from dying.
- Running Gag: Everyone takes a liking to Marlize's macaroni and cheese, even those who haven't actually tasted it.
- Sinister Surveillance: In addition to the spy camera installed in the Samuroid head (which Barry discovers), DeVoe has another in Barry and Iris' apartment.
- Shoo Out the Clowns: Ralph Dibny doesn't appear in this episode. This creates a darker mood.
- Shout-Out: Barry mentions his spidey sense is tingling when it comes to the DeVoes.
- Small Role, Big Impact: It turns out that the man who stole Iris' laptop during "Harrison Wells"' discourse, by taking out Barry and Iris from the scene, has made harder to track DeVoe.
- Stealth Pun: DeVoe listing Barry's past nemeses in reverse. It also might be why Thawne is the only nemesis he lists by name instead of a code name, unlike Savitar and Zoom.
- Stock Unsolved Mysteries: In the flashback, Devoe has used his intellect to figure out that Jack the Ripper was a barber who suffered from delusions.
- String Theory: Barry has set up a new one in his board at CCPD; this time it's dedicated to his (wild to everyone else) accusations against Clifford DeVoe.
- Subverted Suspicion Aesop: Barry relentlessly suspects DeVoe is the villain they're looking for, even going so far as to break into his house to try and gain evidence. No one believes Barry until DeVoe himself confirms his identity to him.
- Surprisingly Realistic Outcome: The Episode! It happens so much that it borders on a Deconstruction. Barry and Joe begin the episode by visiting DeVoe at his house to investigate him. Barry then approaches DeVoe at his place of work. Now given that DeVoe has no criminal record, is in a wheelchair, and hasn't been caught doing anything illegal, it would look to anyone that Barry has no probable cause to investigate DeVoe and DeVoe has every right to claim harassment. Barry then compounds his error by breaking into DeVoe's house, which results in Barry getting suspended from the CCPD, and having DeVoe file a restraining order against him.
- Took a Level in Badass: Even though he ended up in a wheelchair, Clifford became much more efficient in teaching classes after gaining his powers. Before, nobody really paid any attention to him.
- Took a Level in Jerkass: In the flashbacks, DeVoe's number one priority after gaining his powers was to improve the world, while still being a pretty nice guy. In present day, he indulges in Evil Gloating and acts like a Card-Carrying Villain in general.
- Villain Ball: DeVoe just had to reveal his intentions to Barry at the end, despite having a restraining order against Barry that he had just blatantly violated. Assuming, of course, it's not all just part of the plan.
- Villain Episode: Which shows how Clifford DeVoe became what he is.
- We Are Not Going Through That Again: After having to deal with Thawne, Zoom, and Savitar, Barry does not want to go through the year long-process of trying to take down the Big Bad, and wants to stop DeVoe here and now. Unfortunately for him, DeVoe is insanely smart and, like Prometheus was to Oliver, always ten steps ahead.
- Wham Line:
- In-Universe: When Marlize mentions her last name at the press conference, Thawne lights up as he realizes exactly who is in the audience; even he knew the future Thinker would cause Barry much havoc.
- Barry confronts DeVoe at school bluntly asking who he really is. Clifford replies who's asking, "Barry Allen...or the Flash?"
- What the Hell, Hero?:
- Yes, she's probably as malicious and sinister as her husband, but Marlize DeVoe has a valid complaint when Barry breaks into their home.
- Iris, his team and Singh also are in agreement with her, Barry went too far.
- When It All Began: Clifford is yet another victim of Eobard Thawne's Particle Accelerator. He has just been laying low all these years, and only sprang into action now.
- You Have to Believe Me!: Barry's borderline aggressive attempts at convincing the team that DeVoe is the Thinker are certainly not helping his case.
