Supergirl's First Face-Off With Mercy Graves Ends on a Down Note — Watch

The Maiden of Might just might cry Mercy in this sneak peek from the Season 4 premiere of Supergirl, which tonight christens its new Sundays-at-8/7c home.

In the season opener, titled “American Alien,” Kara (played by Melissa Benoist) welcomes cub reporter Nia Nal (transgender actress Nicole Maines) to CatCo, while Alex and Brainy struggle to get in sync in their new roles at the DEO.

The hour’s cold open shows us that Supergirl is finally firing on all cylinders, gleefully pulling double duty and zipping around the globe while her cousin Superman is off-world. Alas, that perfect life balance is threatened when an anti-alien terrorist organization rears its very ugly head in National City.

In the sneak peek above, said organization has targeted an alien friend of J’onn’s, in the course of stealing something from his lab. (Warning: If the lancing of alien appendages that are fake and made out of foam, probably, makes you squeamish, prepare to cover your eyes.)

How does Supergirl’s first face-off with the villain Mercy Graves (The Last Ship‘s Rhona Mitra) and her brother Otis (Grey’s Anatomy‘s Robert Baker) go down? Let’s just say that the Graveses do right by the Scout motto and come prepared!

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