J'onn J'onzz comes face to face with Miss Martian (in her human guise, at least) in a scene from Monday's episode of "Supergirl," titled "Welcome to Earth."

In the clip, which debuted at IGN, Hank Henshaw (David Harewood) visits what looks to be an alien speakeasy, where the bartender (Sharon Leal in her debut as M’gann M’orzz) is caught off guard by the appearance of a Green Martian.

A fan-favorite DC Comics superheroine, Miss Martian was introduced in 2001’s “Teen Titans” #37 as a White Martian who escaped the civil war between her people and the Green Martians. She subsequently gained popularity on the animated series "Young Justice."

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"Welcome to Earth" also marks the debut of Lynda Carter as the U.S. president, who's the target of an attack as the fight about alien-vs.-human rights issues boils over in National City. Supergirl and the Department of Extra-Normal Operations are assigned to protect the president and track down the culprit behind the attack, leading Alex to team up with Detective Maggie Sawyer as Kara looks for the recently escaped Mon-El, whom she feels may be behind the assault.

Airing Mondays at 8 p.m. ET/PT on The CW, “Supergirl” stars Melissa Benoist, Mehcad Brooks, David Harewood, Chyler Leigh and Jeremy Jordan. In addition to Sharon Leal, "Welcome to Earth" also features Floriana Lima and Chris Wood.