Barry's time traveling comes back to haunt him in next week's episode of "The Flash," when a ghostly time wraith follows him from the present to the past, threatening all reality.

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Eddie Thawne, the Pied Piper and what appears to be the original Eobard Thawne incarnation of Harrison Wells are all featured in the promo for "Flashback."

After the shocking revelation that Zoom is Jay Garrick, Barry is more determined than ever to get back to Earth-2 to stop Zoom forever. Desperate to find a way to increase his speed, Barry decides to travel back in time and masquerade as his earlier self in order to get his arch-nemesis, Dr. Harrison Wells/Eobard Thawne, to teach him how to run faster. However, things don't go as planned and Barry is stunned to face a familiar foe Hartley Rathaway, as well as an old friend Eddie Thawne, Iris makes peace with her past in order to embrace her future.

Starring Grant Gustin, Carlos Valdes and Jesse L. Martin, "The Flash" airs Tuesdays at 8 pm EST on The CW.