Well, this should be interesting. I thought they'd wait a year.
Supergirl is a far better show than Flash, and I don't want Flash's mediocre writing to infest my new favorite show, so hopefully they'll keep that quarantined.
It'll probably be something like this:
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"Hark! A super-powered enemy! Stop, cretin!"
:::Supergirl and Flash fight:::
:::Villain shows up:::
:::Supergirl and Flash team up to fight villain:::
"We only have 12 hours to get Flash back to his world before the breach closes!"
:::Sexual tension between Flash and Supergirl; they sing "You're the One That I Want" from Grease; Adam weeps, and shouts "That's our song!":::
"Bye, Flash!"
:::Flash jumps through the breach just in time.:::
"Will we ever see the Flash again?"
"Now that a breach has been opened between our worlds, it's more likely that that breach will open again some day. Now let's order pizza and get back to our own plot lines!"
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