SPOILER WARNING: This article contains major spoilers for "Gone Rogue," the latest episode of The Flash.
Team Flash has finally uncovered Cicada's plan. In "Gone Rogue," the latest episode of The Flash, the team realized Grace wanted to use a broken version of Cisco's cure to kill all the metahumans in Central City.
After Grace broke into Icicle's lab in the Arctic, Caitlin and Ralph traveled there to see what she took. They soon discovered she had stolen Cisco's prototypes for the metahuman cure. These cures had failed, which has fatal implications for anyone subjected to it.
"We figured out what Cicada took from my dad's lab. It's your cure prototypes," Caitlin revealed.
"They're not just prototypes," Cisco said, alarmed. "They're failed, broken versions of the cure. If a metahuman takes that without the proper treatment --"
"They would die," Sherloque finished for him. "Cicada has a lethal virus on her hands."
"That's why she stole the atomizer," Ralph pointed out. "So she can spread the virus."
"She has weaponized the cure," Sherloque confirmed.
"Cicada's gonna kill every metahuman in the city," Barry added with dread.
As such, Grace has both the methods and the means to kill all the metahumans in Central City. Since she is a metahuman as well, this means she likely does not intend to survive the outcome. However, her younger self is safely outside the city, so she will survive to adulthood in the present timeline. This means she can continue the timeloop, in that she will grow up to become Cicada and then commit this act of genocide.
As a result, Team Flash will usher all the metahumans to the Central City Police Department. As glimpsed in the promo for "The Girl With the Red Lightning," next week's episode, this could backfire spectacularly on them. By bringing all the metahumans to one place, they may have just made Cicada's job a whole lot easier.
Airing Tuesdays at 8 p.m. ET/PT on The CW, The Flash stars Grant Gustin, Candice Patton, Carlos Valdes, Danielle Panabaker, Tom Cavanaugh, Jesse L. Martin, Danielle Nicolet, Hartley Sawyer and Jessica Parker Kennedy.