Ricci will play Siobhan Smythe, aka the Silver Banshee. Siobhan is Cat Grant's (Calista Flockhart) newest hire and a menace to Kara (Melissa Benoist) at work (the girl just can't catch a break!). She's an even worse nemesis for Supergirl when she becomes Silver Banshee.
"We are so excited to be working with Italia. We've been a fan of her work for years and we cannot wait to see her take on this iconic comic book role," says executive producer Andrew Kreisberg in a statement.
In the DC comic books, Silver Banshee originated as a foe for Superman and eventually takes over the body of Supergirl's best friend. However, in a new comic thread - The New 52 -- Shiobhan Smythe is actually a friend of Kara's before she transforms into the Silver Banshee. In the comics, Smythe is gifted with the abilities of super strength, and agility along with her hypersonic wails and sonic screams that can kill anyone in a certain range.
Ricci herself is no stranger to the DC universe. Her fiancé Robbie Amell played Firestorm on The Flash in Season 1, and her brother-in-law-to-be Stephen is of course Oliver Queen on Arrow. That makes her the third Amell family member to join the superhero world, but it remains to be seen if Ricci will turn out to be friend or enemy to fight for good.
Supergirl airs Mondays at 8/7c on CBS
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