SPOILERS AHEAD!!! IF YOU HAVE NOT SEEN THE FLASH SEASON 2 EPISODE 13 DO NOT READ ANY FURTHER.
Last night as I was watching the latest episode in The Flash titled "Welcome To Earth-2" I noticed something very interesting. So last week we heard that The Flash and Supergirl will crossover at some point in which it will be during Supergirl's 18th episode. We know that Supergirl, the DCEU (DC Extended Universe), The Flash, Arrow, and Legends of Tomorrow are all part of this multiverse meaning that Supergirl is either in another earth or in an alternate timeline.
Ok, so this episode Barry, Cisco, and Harrison "Harry" Wells go to Earth-2 to try and stop Zoom and save Harry's daughter. We all know that in episode 12 Barry is closing all the breaches to the other earths except for Earth-2. Also in a previous episode the Reverse Flash makes someone create a speed cannon so that he can go back to his timeline. Well, Barry, Cisco, and Harrison use this speed cannon to travel to Earth-2, but before they do that Jay Garrick tells Barry to keep running and to not get distracted by what they will see ahead. Cisco then asks, "What are we going to see?" Jay Garrick replies, "Everything". Well, Jay Garrick was right because once Barry grabs on to Harrison and Cisco he starts running through the portal in which there are images of people in which one of them is Supergirl. Check out the picture and video below of the hinting of Supergirl:
This video above me is the 1st appearance or hint of a Flash/Supergirl crossover.
After seeing this video I am proud to say that the creators of both Supergirl (TV Show) and Flash (2014 TV Show) were right about Supergirl being in a different universe or earth in which Flash will most likely end up traveling to it. This is a very big hint that we will be seeing both shows crossover. Mark your calender's for March 28 as both shows will crossover into an amazing episode!!
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