DC's Legends of Tomorrow S05 E01 Crisis on Infinite Earths: Part Five (V)

"A roaring rewind."

“Worlds lived, worlds died. Nothing will ever be the same.” The crossover starts on Supergirl S05E09 Crisis on Infinite Earths: Part One (I), Batwoman S01E09 Crisis on Infinite Earths: Part Two (II), The Flash S06E09 Crisis on Infinite Earths: Part Three (III) and Arrow S08E08 Crisis on Infinite Earths: Part Four (IV)