American Alien

Synopsis
Diving back into reporting, Kara welcomes a new cub reporter to CatCo. Meanwhile, James and Lena argue about James’ impending indictment for acting as the vigilante Guardian, while Alex and Brainy struggle to get in sync at the DEO. Supergirl is called into action when remnants of the anti-alien terrorist organization Cadmus try to assassinate pro-alien leaders, but their endgame turns out to be much more sinister than she expected. J’onn relishes his peaceful new life, but an outing with an old friend causes him concern.

Trivia

 * Lillian quips that her heart has "grown several sizes" in prison, to which Lena calls her "the Grinch Who Stole Christmas", referencing the protagonist of the Dr. Seuss book How the Grinch Stole Christmas!.
 * Lena claims to Diaz that the new evidence against Bruno will put the latter behind bars for as along as Al Capone.
 * +In the comics, Bruno "Ugly" Mannheim was the leader of Intergang and an enemy of Superman. Bruno's Earth One counterpart was also mentioned in the Arrow Season 6 episode.
 * Sam Witwer and Tiya Sircar both done voice work for several Star Wars animated shows.
 * Supergirl marks Vincent Gayle second Arrowverse appearance. He previously played Pyotr Friedkin in the Arrow episode.