SPOILER WARNING: This article contains major spoilers for "Seeing Red," the latest episode of The Flash.
The Flash may have just deduced a way to stop Cicada once and for all. In "Seeing Red," the latest episode, Barry Allen was challenged in a way he'd never experienced before when Cicada broke Nora's back. His subsequent rage led him to identify with Cicada, which made him realize that saving Cicada's niece Grace may be the only way to stop him.
The episode saw Barry grappling with his rage over the fact Cicada had hurt his daughter so badly. He spent the rest of the episode impatient and short-tempered; even as he attempted to save Central City's metahumans, he snapped at them and took his anger out on them.
With her empath abilities, Cecile realized Barry wanted to kill Cicada. While he denied that at first, he came very close to killing Cicada when push came to shove. As Killer Frost held Cicada's dagger back with her ice powers, Barry used his abilities to brutally beat Cicada and would have killed him if Nora hadn't shown up to stop it. Nora's intervention led to Cicada's escape, but the incident taught Barry an important lesson.
Later, as Barry reflected on the mission with Iris, he was struck by an epiphany. If he wanted to stop Cicada, all they had to do was cure Grace. After all, that's why Cicada has been fighting all along; he wants revenge for his niece, who was hurt in a metahuman incident. Worse, his friend Dr. Ambres has been stoking his rage and hatred all along. Now that Team Flash has discovered the heart of the issue, though, the end of Cicada's mission may finally be in sight.
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.