When Barry turns to Hartley for help in the upcoming Season 6 episode called “Pay the Piper,” he’ll discover that The Flash and Pied Piper (Andy Mientus) are enemies on Earth Prime thanks to the Crisis reset.
The “Crisis” crossover really is the gift that keeps on giving villains to The Flash!
Hartley Rathaway — became an ally of Team Flash due to some timeline changes, and even was in on Barry’s secret.