After dealing with the killer telekinetic gorilla Grodd a.k.a. Wells' means of distracting Barry and the team, The Flash heads off to square off against the Reverse Flash. But he won't do it alone. The Scarlet Speedster teams up with super friends and unlikely foes to defeat this baddie from the future. 

The penultimate episode of "The Flash" season 1 titled "Rogue Air" has Captain Cold's involvement all over it. The last time The Flash saw him was when Barry let him go in exchange for keeping his identity a secret. Freeing Captain Cold turns out to be useful for the fastest man alive, at least initially. 

Captain Cold just can't be trusted (Joe and Caitlin tried to tell Barry that) and in the next episode, Barry realizes why. The idea of the team-up seems to be simply out of his desperation and the fact that Eobard Thawne is not at all be easy to defeat, even with lightning speed. 

The wily rogue found this as an outlet for more troublemaking and by that, Captain Cold means releasing meta-human prisoners from STAR Labs and uniting them with one goal — to settle the score with the red-clad speedster who tossed them in the containment cells.

Good thing though, The Flash eventually realizes that Captain Cold is a baddie for a reason so he rushes to get help from Firestorm and Arrow instead, which means another super-powered crossover. Together, the superheroes do everything in their power to bring down the Reverse Flash and at long last, bring the ever elusive and well-deserved justice for Nora and Henry Allen and bring peace to the life of their son, who let his life be driven by the tragedy. 

"The Flash" season 1 episode 22 titled "Rogue Air" will air on May 12.