We all knew (hoped) that it would happen eventually, and now it has finally come, ‘Supergirl’ is going to have an episode (airing March 28th) where Barry Allen crosses over from ‘The Flash’ to lend her a hand with two super villains, thus cementing her place in the Arrowverse.
Source: Flashy Crossover: Cast And Crew Of ‘Supergirl’ Tease Crossover With ‘The Flash’
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