Kara gains a new ally when the lightning-fast superhero The Flash 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.
Quest roles:
Grant Gustin(Barry Allen / The Flash), Brit Morgan(Leslie Willis / Livewire), Chris Vance(Non), Jenna Dewan(Lucy Lane), Italia Ricci(Siobhan Smythe / Silver Banshee), Christopher Showerman(Tor), Harriet Sansom Harris(Sinead), Jay Jackson(News Anchor), Sarah Robson(Dr. Amelia Hamilton), Dan Warner(Fire Chief), Dawn Greenidge(Pedestrian Woman)