As the "Arrow" spin-off TV series "The Flash" climbs towards its premiere, more casting news has surfaced.

For those wondering about mysterious S.T.A.R. Labs Particle Accelerator, "The Flash" TV series will soon debut the rock star scientist behind it.

TVLine reports that actor Tom Cavanagh will play Harrison Wells, the mastermind behind the Particle Accelerator. After the explosion which becomes the catalyst for Barry Allen's transformation.

In "The Flash" TV series, Wells will be alienated due to the failure of the Particle Accelerator, but that will all change once he discovers Barry Allen's speedy ability.

Cavanagh will join Grant Gustin (Barry Allen), Candice Patton (Iris West), Jesse L. Martin, Carlos Valdes, Daniele Panabaker, and Rick Cosnett.

Due to the popularity of "Arrow," fans are already getting the jitters "The Flash" will be canceled and Grant Gustin will be lost forever.

Fortunately, Screen Crush reports that executive producer Greg Berlanti will continue to utilize Barry Allen, whether on "The Flash" or "Arrow."

“Fingers crossed we don’t screw it up and he gets his own show!" says Berlanti to Digital Spy.

“If he didn’t, I don’t think we would ever want to let Grant go. He’s too valuable. That would be our hope, I think – no matter what, to keep Barry part of the universe.”