Flash Supergirl Crossover

Kara gains a new ally when the lightning-fast superhero The Flash (Grant Gustin) 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 at 8/7c.

CBS has released the trailer for “World’s Finest,” which finds Barry Allen trapped on Supergirl’s world. The video glosses over how Barry got there and how he came to be on a first name basis with Melissa Benoist’s Kara. Instead, it jumps to instant camaraderie between the two heroes as they team up to take down Silver Banshee and Livewire. The episode airs Monday March 28th.