The Flash Season 2: 28 Easter Eggs & References You Might've Missed
6. Ace Chemical
When Barry is fighting Grey Griffin, the villain leads him to Ace Chemical, which is where he had his accident.
While setting up his origin story, it's also borrowing something from another, much more well-known story in DC Comics.
Ace Chemicals was the location for the Joker, then as the Red Hood, falling into a vat of chemicals that gave him his green hair, chalk white skin, and red lips.