'Supergirl': Mercy Graves Attacks in "Fallout" Synopsis

The CW has released a new synopsis for "Fallout", the second synopsis of Supergirl's fourth season.

The synopsis hints at Mercy Graves (Rhona Mitra) catching the attention of Supergirl (Melissa Benoist) and the DEO, although it might not be under the best circumstances.

"CHAOS IN NATIONAL CITY — A shocking revelation causes chaos in National City. Supergirl (Melissa Benoist) sets out to capture Mercy Graves (guest star Rhona Mitra), while Alex (Chyler Leigh) takes control at the DEO. Back at CatCo, Kara decides to write an investigative story on Mercy and asks Lena (Katie McGrath) if she can interview her as Mercy has ties to the Luthors.

Meanwhile, Brainy (Jesse Rath) meets Nia (Nicole Maines) and the two end up in a precarious situation.

Harry Jierjian directed the episode with story by Dana Horgan and teleplay by Maria Maggenti & Daniel Beaty."

It's unclear exactly how Mercy's storyline will factor into Season 4 -- especially with the other plot threads that are currently dangling -- but it sounds like the Girl of Steel will be having a new approach to how to take her on.

"With decisions she makes and how things transpire to wrap it up, she's really taking ownership of herself," Benoist said in an interview earlier this year. "She's maturing, which is what I've always wanted for her since season 1. I wanted to see a natural arc of a girl coming into womanhood, because she was almost naive at the beginning, and just charging ahead not really knowing what she was doing. And now, I think she really does, and she is slowly chiseling out her place, wherever she wants to be."

And as Supergirl makes its way into Season 4, it sounds like that new place for Kara will come with a bit more social justice commentary as well.

"The writer's room is being really great this year," Benoist said in a recent interview. "Last season, it was a lot of fire and brimstone and a lot of homages to Buffy the Vampire Slayer, which was great because I was such a big fan of that show. This season they really want to thematically tackle more topical stories that maybe mirror what's going on with the state of the world and our country. There's a lot of anti-alien sentiment at the beginning of Season 4 that Supergirl is going to have to grapple with. I think their main premise is that fear itself is a villain and can hope conquer it? Supergirl stands for hope, so we'll see. I think fear is her biggest opponent yet because it's more of a wildfire-type emotion."

What do you think of Supergirl's newest synopsis? Share your thoughts in the comments below.

"Fallout" will air on Sunday, October 21st, at 8/7c on The CW.