"""Worlds Finest"" -- Kara (Melissa Benoist, left) gains a new ally when the lightning-fast superhero The Flash (Grant Gustin, right) suddenly appears from an alternate universe and helps Kara battle Siobhan, aka Silver Banshee, and Livewire in exchange for her help in finding a way to return him home, on SUPERGIRL, Monday, March 28 (8:00-9:00 PM, ET/PT) on the CBS Television Network.  Photo: Robert Voets/Warner Bros. Entertainment Inc. © 2016 WBEI. All rights reserved."
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