Just hours after Victor Garber signed on to play Dr. Martin Stein in The CW's The Flash, the show has also added Andy Mientus as Harley Rathaway, a.k.a. The Pied Piper.

We first reported on The Pied Piper's involvement in the show last month, who is one of the original members of the Rogues. That supervillain group is formed by Captain Cold (Wentworth Miller), who will be introduced in the show's fourth episode, "Going Rogue" on October 28. As for The Pied Piper, he will appear in the show's 11th and 12th episodes this season.

In the show, Harley Rathaway is a true genius who used to work at S.T.A.R. Labs until he had a falling out with Tom Cavanagh's Harrison Wells. The particle accelerator explosion that turned Barry Allen (Grant Gustin) into the show's title character also robbed Harley of his hearing. He seeks revenge on Wells by creating a series of sonic weapons as he tries to destroy The Flash. In the DC Comics, The Pied Piper was one of the first openly gay characters, and this aspect of his life will also be featured on the show.

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Andy Mientus is best known for playing Kyle Bishop on the NBC series Smash, and he has also guest-starred on FX's Anger Management and ABC Family's Chasing Life.

In related news, The CW has released the official plot synopsis for The Flash's third episode, "Things You Can't Outrun", airing Tuesday, October 21, which teases the arrival of The Mist and Ronnie Raymond.

"As Barry (Grant Gustin) and the team at S.T.A.R. Labs work to capture Kyle Nimbus (guest star Anthony Carrigan), a.k.a. The Mist, a dangerous new meta-human with toxic gas powers, they revisit the painful night the particle accelerator exploded and killed Caitlin's (Danielle Panabaker) fiancé, Ronnie (guest star Robbie Amell). Meanwhile, Joe (Jesse L. Martin) decides to finally visit Henry (John Wesley Shipp) in jail after all these years, but things take a dangerous turn when Kyle shows up looking to punish Joe for arresting him years ago. Meanwhile, Iris (Candice Patton) and Eddie (Rick Cosnett) continue to hide their relationship from Joe. Jesse Warn directed the episode written by Alison Schapker & Grainne Godfree."

Finally, illustrator John Gallagher debuted a new banner for The Flash, which you can see below the message he posted on his Deviant Art page.

"So last night after much buzz and fanfare was the premiere of The Flash and I couldn't be prouder of the team and the show we're putting together. While I didn't work on the pilot - it's almost always a different team - the series has been an absolute pleasure to be a part of. I'm surrounded by the best around and we all have a pretty good feeling about what we're building. I'll be able to post some images in a few days. Be sure to check it out!"
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