Supergirl: A White Martian Attacks in 'Martian Chronicles' Clip, Photos

J'onn J'onzz's speech to M'gann about trust and duty is interrupted by the untimely arrival of a very angry White Martian in a preview of Monday's episode of "Supergirl."

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The CW has also released new images from the episode, appropriately titled "The Martian Chronicles," in which the White Martian comes to National City intent on apprehending M'gann and returning her to Mars, where she's to be punished as a traitor. Of course, Kara and J'onn aren't about to allow that to happen.

WHITE MARTIANS ATTACK THE DEO — Armek (guest star Terrell Tilford), a White Martian, descends on National City intent on taking M’gann (guest star Sharon Leal) back to Mars to face her punishment as a traitor. Hank (David Harewood) and Supergirl (Melissa Benoist) determine the best way to keep M’gann safe is to bring her to the DEO. However, when it is revealed that Armek shape-shifted into M’gann and is now loose in the building, the team realize he could be disguised as any one of them.

Long a threat in DC comics and animation, the subterranean, war-like White Martians were introduced during the first season of “Supergirl,” and became more prominent in Season Two with the introduction of Sharon Leal as M’gann M’orzz, aka Miss Martian.

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Airing Mondays at 8 p.m. ET/PT on The CW, “Supergirl” stars Melissa Benoist, Mehcad Brooks, Chyler Leigh, Jeremy Jordan, David Harewood and Chris Wood.

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