SPOILER WARNING: the following story contains major spoilers for the March 29 episode of "The Flash."


When "The Flash" returns from its mid-winter hiatus, Barry and the rest of his team will deal with a new speedster with criminal leanings and whatever new threat the Pied Piper poses.

Oh, and there's also the return of Eddie Thawne.

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Announced via TV Line, Rick Cosnett reprises his role as Eddie in "Flash Back," the series' March 29 episode. Whether it's as Earth-2's Eddie, in a flashback as the episode title hints, or a result of time travel as indicated in the episode synopsis remains unknown, but considering Eddie died a pretty definitive death, there's obviously a catch to his return.

The episode synopsis reads:

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 familiar foe Hartley Rathaway (guest star Andy Mientus), as well as old friend Eddie Thawne (guest star Rick Cosnett). Iris makes peace with her past in order to embrace her future.

Starring Grant Gustin, Carlos Valdes and Jesse L. Martin, "The Flash" returns Tuesday, March 22 at 8 pm EST on The CW. "Flash Back" airs March 29.