Supergirl and The Flash Crossover: Worlds Finest Key Art and Synopsis Released

CBS broke out a live-action version of Superman #199 -- one of the most oft-homaged DC Comics covers of all time -- this morning, as they revealed key art for "Worlds Finest," the upcoming episode of Supergirl on which Grant Gustin will guest star as The Flash.

They also released the official synopsis, which confirms that the villains will be Silver Banshee and Livewire; announces the introduction of a "Dr. Amelia Hamilton"; and confirms that The Flash and Supergirl live on parallel Earths.

Amelia Hamilton, of course, is a nod to the longtime Superman supporting character Dr. Emil Hamilton, played by The West Wing's Richard Schiff in Man of Steel.

You can check out the full image and official synopsis, along with credits, below. Supergirl's "Worlds Finest" episode airs on Monday, March 29 at 8 p.m. ET/PT on CBS.

"Worlds Finest" – 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 (8:00-9:00 PM) on the CBS Television Network. Grant Gustin crosses over as The Flash.

GUEST CAST:

Grant Gustin
(The Flash/Barry Allen)

Jamie Kaler
(Pundit #1)

Samantha Harris
(Pundit #2)

Zarek King
(Young Boy)

Sarah Robson
(Dr. Amelia Hamilton)

Harriet Sansom Harris
(Sinead)

Dawn Greenidge
(Pedestrian Woman)

STORY BY: Greg Berlanti

TELEPLAY BY: Andrew Kreisberg & Michael Grassi

BASED ON: The Characters Appearing in the DC Comics

DIRECTED BY: Nick Gomez