"The Flash" will return with season 2 on 6 October and ahead of that, The CW has released a new extended trailer, which features the debut of some of the most popular characters from the DC universe. The upcoming season will see more than one Flash, a new well-intentioned police officer and the big bad – bigger and badder than anything we have seen before.

Jay Garrick (Teddy Sears), the first Flash, is fighting a villain named Zoom, and he has come to Central City to warn his successor that by opening the portal, Barry (Grant Gustin) has opened a gate for Zoom. We will see the Flashes working together in an attempt to save their worlds.

Read More: Barry to Fight 'Big Bad' Zoom in October; Who is Hunter Zolomon?

As Garrick explains to Barry, the portal has opened many worlds, in one of which might reside good old Eddie (Rick Cosnett), except he may not be so good anymore. Many fans feel that Eddie might return to "The Flash" season 2 as Cobalt Blue. In a poll we conducted for "The Flash" fans, wherein we asked if Eddie might return, almost 40% felt that he would, while 25% believed he could be the reverse flash.

Popular theory is that the wormhole would give open an entryway for an alternate version of Eddie to appear in Central City. He will get close to Team Flash, and hint about his villainous nature will be dropped, as we get to know more and more about Cobalt Blue.

Read More: Cisco's Future as Vibe; Barry's Trial; Kid Flash in DC's 'LoT'? [VIDEO]

Meanwhile, Cisco (Carlos Valdes) is still getting used to the fact that he is a meta-human. Fans will remember his disturbing yet enticing, flirtatious relationship with Lisa Snart (Peyton List), sister of Captain Cold (Wentworth Miller). 

Lisa, who loves teasing Cisco, may get a taste of her own medicine, when a more powerful and more confident Vibe starts responding to her suggestive comments. When Lisa tells Cisco, " I always did like a man who could handle a gun", Cisco replies, "you should see my nerf collection". 

For more updates on "The Flash" brefore its return to The CW on 6 October, check back here.