Supergirl & Martian Manhunter Unite on 'Martian Chronicles' Poster

Kara and J'onn J'onzz prepare for a showdown with the White Martians in a poster for the Feb. 6 episode of "Supergirl."

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Unveiled by David Harewood, the teaser for "The Martian Chronicles" depicts the actor as Martian Manhunter alongside Melissa Benoist as the Girl of Steel, accompanied by the tagline, "Worlds Clash. Heroes Unite."

The Martian Chronicles. Coming soon.

A photo posted by David Harewood (@davidharewood) on

In the episode, a White Martian arrives in National City to capture M'gann and return her to Mars, where she's to be punished as a traitor. Unwilling to allow that to happen, Hank Henshaw and Supergirl bring M'gann to the Department of Extra-Normal Operations for protection, only for circumstances to turn from bad to worse.

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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