Watch "The Flash" season 2 episode 9 live stream here for free! Watch it all unravel here at Kpopstarz.com. Finally, the mid-season finale is upon us and it will be a busy Christmas season for Barry Allen as he battles three formidable villains in Weather Wizard, The Trickster and Captain Cold.

For CW, there is a live stream of the channel which can be accessed here and here (depending on your region, one may be accessible over the other), and through that, fans can watch "The Flash" season 2 episode 9 live stream online.

Here's the episode synopsis courtesy of Comic Book Resources.

"MARK HAMILL, WENTWORTH MILLER AND LIAM MCINTYRE RETURN; KEIYNAN LONSDALE JOINS THE CAST AS WALLY WEST - When Mark Mardon AKA The Weather Wizard (guest star Liam McIntyre) returns to break Leonard Snart AKA Captain Cold (guest star Wentworth Miller) and James Jesse AKA The Trickster (guest star Mark Hamill) out of Iron Heights, Barry (Grant Gustin) must stop these rogues from taking over Central City during Christmas." 

"Meanwhile, Joe (Jesse L. Martin) and Iris (Candice Patton) meet Wally West (Keiynan Lonsdale)."

This episode will also be Wally West's debut and the stars of the show talked about his arrival. Jesse L. Martin talked about how Joe will react when he first meet his long lost son.

"It's pretty devastating for Joe, because this is an 18-year-old secret that his wife just kept from him, and the fact this boy grew up without a father really rubs Joe the wrong way," Martin tells EW. "It's something that he feels immediately guilty about."

"He almost immediately forgives Iris for lying about that." Martin says. "The reveal is way more important. His mind goes directly to that: Will I be able to have a relationship with this kid, and if so what kind of relationship am I going to have if I haven't been in his life since he grew up?"