Therefore I Am

"Therefore I Am" is the seventh episode of the fourth season of The Flash, and the seventy-sixth episode overall. It aired on November 21, 2017.

Synopsis
Barry comes face to face with DeVoe. DeVoe’s past is revealed through flashbacks. Meanwhile, Iris puts the final touches on the wedding, which is a week away.

Trivia

 * The title is a reference to the philosophical proposition "I think, therefore I am", originally known in Latin as "Cogito ergo sum".
 * Marlize asks Clifford if he's seen a video of a Husky singing the Madonna song "Like a Virgin".
 * Cisco asks Barry if he's seen "Zatoichi the blind swordsman", a franchise of films and a TV series featuring the eponymous character.
 * At the press meeting for Dr. Wells, secretly Eobard Thawne, at the turning on of the particle accelerator, he noted that Barry was present, along with Clifford DeVoe and his wife. Thawne was excited at this and even remarked that he was a fan of DeVoe's and even said 'good luck' to DeVoe for the future, likely because since Thawne was from the future he knew DeVoe would one day become an enemy to the Flash.
 * Similar to the comics, Clifford DeVoe obtains his high levels of intellect through his developed and created: "the Thinking Cap", and he even names it the same. Also like in the comics, its use has detrimental effects on the rest of his body, though instead of a slow cancer like in the comics, it is a fast-acting paralysis.
 * The scene from is shown again, however it continues on at the press conference after Barry runs after the thief.
 * The date of the explosion of the particle accelerator by Thawne occurred on January 7th. DeVoe remarked that both himself and Barry were born on that day in terms of becoming the Thinker and the Flash, respectively.
 * However while the date of the particle accelerator explosion is given as January 7, 2014 in this episode, Felicity Smoak stated in an episode of the animated series Vixen, that the particle accelerator exploded on December 11, 2013. Also, Cisco names the same date in the Broken Arrow.
 * Barry tells Iris that his "Spidey sense is tingling", referencing the Marvel superhero Spider-Man and his powers.
 * When Wally returns, he talks about fighting a giant starfish from outer space. This is a reference to the Justice League villain Starro.