Trajectory


 * For the character this episode is based around, see Eliza Harmon.

"Who the hell are you?"

- The Flash on the female speedster

"Trajectory" is the sixteenth episode of the second season of The Flash, and the thirty-ninth episode overall. It aired on March 22, 2016.

Synopsis
Deciding to blow off some steam, Barry and the team head out for a night on the town only to encounter an unexpected speedster who is up to no good. Iris is challenged by an assignment from her new boss, and is surprised when friction turns to flirtation.

Plot
Barry is desperately training to get faster, going so far as to jumping canyons, which he fails. Back at S.T.A.R Labs, Cisco Says that Team Flash requires a break and suggests the Club, while Wells does not like the idea of Jesse going, he eventually agrees. Jesse, Cisco, Caitlin and Barry meet Iris and Wally at the club and while Cisco and Caitlin dance, Barry and Iris reminisce on the fact that they are married on Earth-2 and in the future. Moments later an unknown Speedster with Flashes lightning robs everyone in the club. Barry chases after her but she escapes. At Central City Picture News, Scott Evens tells everyone that The Flash is now a criminal, while Iris defends him.

At S.T.A.R Labs Team Flash try to understand how the Female Speedster got her powers, Caitlin and Wells tell Barry and the rest of the team about Velocity 9. Barry grows mad at the team for not telling him about a formula that could make him faster, while Caitlin tells Barry that the formula could end up killing him. The team get word on ‘Bad Flash’ and Barry chases after her, in a fight he quickly loses. Caitlin remembers that when designing Velocity 9, she got help from a fellow scientist, Eliza Harmon. Joe and Caitlin investigate the lab though Eliza denies any of the formula in the lab. Later Eliza starts hearing the voice of Trajectory in her head and takes her final Velocity 9 formula. At S.T.A.R Labs Barry steals the final velocity 9 formula, thinking of taking it, though Wells talks him out of it.

Soon Trajectory infiltrates S.T.A.R Labs, puts Flash in the pipeline, knocks Joe out than takes his gun and holds Wells at gunpoint and requesting more Velocity 9. After holding Jesse at gunpoint, Wells makes more of the Velocity 9 and after making sure it’s real, Trajectory leaves. After a while, the team find out she is attempting to make a bridge collapse, which it does after Flash gets all the civilians off. Barry finds out he has to go Mach 3.3 to jump the bridge, which he achieves and beats Trajectory. He gives her the chance to beat her addiction and prove stronger than Velocity 9, but she refuses. She takes another formula and her lightning turns blue and she degenerates.

Back at S.T.A.R Labs, the team start having suspicions that Jay is Zoom and after Cisco vibes his helmet, they come to the conclusion that the theory is true. Barry, devastated by the revelation, speeds off back to the canyon where he previously trained and screams towards the sky.

Trivia

 * Dr. Wells claims that "nothing in life is promised except death". When asked if he is quoting Edgar Allen Poe, he replies with Kanye West, the former might be a slightly reference to actor Tom Cavanagh's role at Fox series The Following.
 * After watching a documentary on singer Beyoncé, Jesse Quick remarks that they must mean "Senator Knowles", from her Earth.
 * This episode marks the first appearance of a female speedster of the series.
 * When Joe West first introduces himself to Eliza Harmon as a detective, she responds, "How very Law and Order of you." Jesse L. Martin, the actor who plays Det. Joe West, starred as Detective Ed Green on the TV series Law & Order from 1999 to 2008. Danielle Panabaker also starred in an episode of Law and Order: Special Victims Unit.
 * Cisco is seen dancing in this episode. In the pre-New 52 comics, Vibe is known as a break-dancer.
 * The concept of a rival speedster destroying a bridge through friction was demonstrated in the comics when Bart Allen- Barry's grandson and the active Flash- was confronted by rival new 'hero' the Griffin, who sought to destroy the bridge with the goal of saving those on it to affirm his status as a 'hero', only for Bart to stop the bridge from falling in the first place by repairing the damage at superspeed.