While Iris’ (Candice Patton) time sickness bounces her to the future where struggle to find a way to help, that same condition has affected the negative version of the Forces (Sara Garcia, Ennis Esmer, and Christian Magby) who make a trip to Lian Yu to kill Eobard Thawne (Tom Cavanagh) and then to S.T.A.R. Labs to kill the younger version (Matt Letscher) as well. In need of more speed, Barry‘s (Grant Gustin) training of Fast Track (Kausar Mohammed) takes a turn when he teaches her how to share her speed with Eobard (a really, really, really bad idea the episode races through without a second thought) leading to the apparent death of a major character and rebirth of another in the cliffhanger ending of “Part One.”
In the second-half of the finale Barry plans for revenge by entering the Negative Speed Force despite the concerns of Cecile (Danielle Nicolet), Nora (Jessica Parker Kennedy), and Bart (Jordan Fisher). Meanwhile, the disembodied spirit of Iris finds herself trapped in the Time Stone with Damien Darhk (Neal McDonough), and a new super-powered Thawne returns to Central City. It will take a super-powered Flash to stop him and avoid an Armageddon. Other stories involve Caitlin (Danielle Panabaker) working with Chillblaine (Jon Cor) to bring back Frost, and Cecile testing her new stolen powers which continue to build on each other making her more powerful and the key to get in contact with the positive Forces.
