“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.”
Supergirl stars Melissa Benoist in the title role, Mehcad Brooks as James Olsen, Laura Benanti as Alura Zor-El, Calista Flockhart as Cat Grant, Chyler Leigh as Alexandra “Alex” Danvers, Jeremy Jordan as Winslow “Winn” Schott, Jenna Dewan Tatum as Lucy Lane (sister of Lois), David Harewood as Hank Henshaw, Peter Facinelli as Maxwell Lord, with Dean Cain and Helen Slater. Supergirl season two features recurring roles for Katie McGrath as Lena Luthor, Floriana Lima as Maggie Sawyer, and Lynda Carter as the President of the United States.