IN PHOTO: Cast Member Grant Gustin Attends A Panel For The CW Television Series 'The Flash.'
IN PHOTO: Cast member Grant Gustin attends a panel for The CW television series "The Flash" during the Television Critics Association Cable Summer Press Tour in Beverly Hills, California July 18, 2014. MARIO ANZUONI/Reuters

"The Flash" Season 1, Episode 9, titled "The Man In The Yellow Suit," airs this Tuesday, Dec. 9, on The CW. In this week's new episode, Reverse Flash makes an appearance again, and Barry Allen is hopeful that sightings of his nemesis would bring his father closer to freedom. Meanwhile, Firestorm is resurfacing soon to give Caitlin the shock of her life.

Spoiler alert: This update contains The Flash spoilers. Read at your own risk.

"Barry faces his nemesis Reverse Flash, who killed his mother, and plots with Wells (Tom Cavanagh) and Cisco (Carlos Valdes) to trap him. Meanwhile, Eddie (Rick Cosnett) gives Iris (Candice Patton) a surprising gift at Christmas and leaves her with a question that could change her life," reads the episode synopsis of The Flash Season 1, Episode 9 on TV.com.

"Barry will actually get to come face to face with [Reverse Flash], not just running with him, but standing face to face with him, looking at him," Gustin told Entertainment Weekly, in an interview about the identity of Barry Allen's nemesis.

"I didn't even remotely see coming what [showrunner] Andrew Kreisberg told me is going to be one of the turning points with [the Reverse Flash] storyline," Gustin said, adding, "no one knows what's going on." This is his reaction to speculations on the identity of Reverse Flash.

"Andrew told me [who is Reverse Flash] and I was like, 'Holy crap,'" the actor told EW.

Meanwhile, Danielle Panabaker, who plays Caitlin Snow, spoke to TV Guide about her character's believed-to-be-dead fiancé, Ronnie Raymond (Robbie Amell). Ronnie showed up as Firestorm toward the end of The Flash Season 1, Episode 8 ("Flash vs Arrow").

Panabaker said Caitlin would be struck by "trauma" when she realizes that Ronnie is (somewhat) alive.

"Maybe she's losing her mind thinking he's coming back to life," Panabaker said.

Ronnie Raymond and nuclear physicist Dr. Martin Stein (Victor Garber) are fused together in one metahuman body as a result of the explosion of Dr Wells' particle accelerator. There is nothing about Firestorm in The Flash winter finale synopsis, but fans are thrilled, nonetheless.

Robbie Amell talked about his costume as Firestorm in this Access Hollywood interview. The actor was last seen on the now defunct "The Tomorrow People" (also aired on The CW).

The Flash Season 1 is taking its winter break after Episode 9. In 2015, Mark Hamill will join the cast as James Jesse, aka the Trickster. Hamill's role reprisal was first reported by HitFix.

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