"The Flash" star Grant Gustin offered a little preview of his trip to "Supergirl's" world with a new photo on his Instagram. The snapshot features both Gustin and Melissa Benoist standing side-by-side in costume.

"Those two emblems look pretty good together," he wrote.

Gustin will appear as The Flash on the March 28 episode of "Supergirl." Details on the episode -- including the plot, how exactly Barry Allen finds himself in "Supergirl" territory and the extent of his role in the episode -- have not yet been released.

Those two emblems look pretty good together... @melissabenoist A photo posted by Grant Gustin (@grantgust) on

He also snapped a picture of his chair on "Supergirl" with a tongue-in-cheek message to "The Flash's" producers.

Hey Flash producers... I've already got a fancier chair on Supergirl than I've got on Flash. Just saying... A photo posted by Grant Gustin (@grantgust) on

Starring Grant Gustin, Carlos Valdes and Jesse L. Martin, "The Flash" returns airs Tuesdays at 8 pm EST on The CW.

"Supergirl" airs Mondays at 8 pm EST on CBS. Developed by producers Greg Berlanti, Ali Adler and Andrew Kreisberg, the series stars Melissa Benoist, Calista Flockhart, David Harewood and Chyler Leigh.