Barry Allen Meets Kara in New Supergirl Crossover Photos

"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: Michael Yarish/Warner Bros. Entertainment Inc. © 2016 WBEI. All rights reserved.

Barry Allen Meets Kara in new Supergirl crossover photos

Following the first official promo that debuted earlier, CBS  has revealed the first official Supergirl crossover photos featuring Grant Gustin as Barry Allen! Check them out in the gallery below.

Episode 18 of Supergirl is appropriately titled “World’s Finest” and is officially described as follows:

“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.”

Melissa Benoist leads the cast of Supergirl as the title character alongside Mehcad Brooks as James Olsen, Laura Benanti as Alura Zor-El, Calista Flockhart as Cat Grant, Chyler Leigh as Alexandra “Alex” Danvers, Jeremy Jordan as Winslow “Winn” Schott, Jenna Dewan Tatum as Lucy Lane (sister of Lois), David Harewood as Hank Henshaw, Peter Facinelli as Maxwell Lord, with Dean Cain and Helen Slater.

The Flash and Supergirl crossover is set to air Monday March 28 at 8 PM ET on CBS. If you missed an episode of Supergirl, or just need a refresher, be sure to check out our weekly recaps by clicking here and read our recaps of The Flash by clicking here.