After nearly a year of speculation and weeks of anticipation, Grant Gustin -- The CW's "The Flash" -- will cross networks to bring Barry Allen to CBS' "Supergirl" this Monday, in an episode titled "Worlds Finest."

In a new behind-the-scenes video released by CBS, "Supergirl" star Melissa Benoist, Gustin, Mehcad Brooks (James Olsen) and Jeremy Jordan (Winn) all share their enthusiasm for the crossover. "It's just so cool," Benoist exclaims.

"What's kind of great about this episode is that they help each other," Benoist says in the video. "[Barry's] been spending the last year and a half exploring his powers, and now he's here to share his wisdom with Kara," Gustin adds.

During a time where representation of DC Comics heroes on the big screen has received criticism for being too dark for some fans' tastes, both Benoist and Gustin highlight the relatively light touch of their characters.

"They have such good chemistry because there's this joy about them; humor and lightheartedness," Benoist says. "It just felt like we were literally living a comic book, bringing it to life."

"Worlds Finest," featuring Gustin as The Flash meeting "Supergirl" for the first time, is scheduled to air 8 p.m. Monday, March 28 on CBS.