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.false2018-11-03 16:34:10Worlds FinestNick GomezGreg BerlantiAndrew KreisbergMichael GrassiGreg BerlantiAndrew KreisbergMichael Grassi7.6201644https://www.thetvdb.com/banners/episodes/295759/5503529.jpgGrant GustinActorhttps://image.tmdb.org/t/p/original/ynf7xAVm6p3MmuLl8SjZnIRR4Zo.jpgJenna Dewan-TatumActorChris VanceActorItalia RicciActorhttps://image.tmdb.org/t/p/original/c2hdp1feyjdjBdTzrLwnnlNBsO4.jpgBrit MorganActorhttps://image.tmdb.org/t/p/original/wbvokHuEX42Zv7euxhW3yo6sJ76.jpgChristopher ShowermanActorhttps://image.tmdb.org/t/p/original/x2CPd7YaCKPuBP4SmWNZTeHy1Cq.jpgSarah RobsonActorHarriet Sansom HarrisActorhttps://image.tmdb.org/t/p/original/1ShvYCWkZycAGb27ZivGrLx1PhS.jpg1812016-03-28122957595503529HDTV