Episode BreakdownTV Show:The Flash (2014) Season: 3 Episode: 21 | S03E21 Air Date: 9 May, 2017
The Flash (2014) S03E21 - Cause and Effect
Cisco comes up with a plan to stop Savitar involving preventing Barry from forming short-term memories. However, the plan doesn't go as intended. Meanwhile, Killer Frost returns to S.T.A.R. Labs to help the team.