Smallville (2001)

S4E10 Scare

A toxic substance from a Luthorcorp experiment is unleashed into the air, triggering intense hallucinations of personal fears in its victims. Chloe, Clark, Lana, and Jason succumb to the effects of the toxin. In a race against time, Lex resorts to a perilous antidote in hopes of saving them. Concurrently, Lionel is freed from prison after his conviction is annulled, thanks to the intervention of an enigmatic supporter.