Question: what episode does lucifer appear in crisis on infinite earths?
Answer: How That Lucifer 'Crisis on Infinite Earths' Cameo Came About. [Warning: The below contains MAJOR spoilers for Season 6, Episode 9 of The Flash, "Crisis on Infinite Earths: Part Three."] The devil doesn't lie ... except when he does to keep his appearance in the epic CW crossover a secret.