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I was trying to watch s04e08 of The Flash and I realised that the storyline was based on something that began from another CW show. I've seen this before but, it began with The Flash so it was easier to follow. I checked The Arrow s06e08 and it seemed to be another continuation. What's the cross over sequence to follow whats happening on The Flash?

marked as duplicate by Ankit Sharma Dec 8 '17 at 5:41

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

The order is as follows:

  1. Supergirl S3E8 Crisis on Earth-X Part-1

  2. Arrow S6E8 Crisis on Earth-X Part-2

  3. Flash S4E8 Crisis on Earth-X Part-3

  4. Legends of tomorrow S3E8 Crisis on Earth-X Part-4

Then watch Flash Episode 9

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