Last month, it was confirmed that CBS' new hit DC Comics superhero series Supergirl will be crossing over with The CW's The Flash in a special episode set to air Monday, March 28. Since then, we've gotten our first look at Grant Gustin's Barry Allen in photos from the set. Today, we have the first official poster and plot details from this episode, entitled World's Finest. CBS gave the following official synopsis, which arrives with a one-sheet that is a parody of the iconic Superman #199 cover from DC Comics.

Hold onto your capes and dust off your running shoes because we've got new intel on the epic Supergirl / The Flash crossover, which airs Monday, March 28 on CBS. In the episode entitled World's Finest, Supergirl joins forces with a lightning-fast-and super dreamy-hero, The Flash (Grant Gustin), to take out two villains. Lost and confused after spiraling from his universe and landing in Kara's, The Flash asks for her help in finding his way back home.

Excited to finally come face-to-face with one of the good guys, Kara agrees on one condition: The super-runner has to help her take down her ultra-competitive co-worker and screeching malefactor Siobhan, aka Silver Banshee, and Supergirl's old nemesis, Livewire. Packed with action, excitement, and a bit of super-flirting, this is an episode you do not want to miss. Italia Ricci returns as Silver Banshee alongside Brit Morgan as Livewire.

This episode will also feature recurring Supergirl stars Jenna Dewan-Tatum as Lucy Lane, Chris Vance as Non and Christopher Showerman as Tor. Ever since Supergirl was picked up by CBS, fans had wondered if it was possible for this series to cross over with Greg Berlanti and Andrew Kreisberg's shows Arrow and The Flash on The CW. While they do air on different networks, both CBS and Warner Bros. Entertainment actually own The CW, with the network's name a combination of the first letters of its parent companies.

Supergirl stars Melissa Benoist, Mehcad Brooks, Chyler Leigh and Jeremy Jordan, with David Harewood and Calista Flockhart. The series is produced by Berlanti Productions in association with Warner Bros. Television. Greg Berlanti, Ali Adler, Andrew Kreisberg and Sarah Schechter are the executive producers of Supergirl, based on the characters appearing in DC Comics, and created by Jerry Siegel and Joe Shuster, by special arrangement with the Jerry Siegel Family. Take a look at the poster to get ready for this epic crossover event at the end of this month.

Flash <strong><em>Supergirl</em></strong> Crossover Episode Poster

Flash <strong><em>Supergirl</em></strong> Crossover Episode Poster