Mxyzptlk returns with a proposition for Kara – what if she could go back in time and tell Lena her secret before Lex did, would things turn out different? Looking…

When Tanya, a disciple of Coville’s, escapes from what’s left of his cult, she gives Kara and James a journal that could hold the key to saving Sam. Someone learns…

Kara makes a major life decision. Meanwhile, J’onn finds out that special DEO-caliber guns have hit the streets of National City.

Supergirl learns the true depth of Serena’s nefarious plans for Earth. Supergirl, Mon-El and Alura must devise a plan to stop her before Serena gets to Earth. J’onn prepares to…

Supergirl and team take on Selena in an epic battle for Earth.

Kara investigates a secretive new group whose leader, Thomas Coville, has a mysterious connection to Supergirl. Meanwhile, Samantha feels like she’s letting Ruby down, and J’onn confesses an old secret.

Supergirl investigates a mysterious symbol popping up all over National City, tracing its origins back to an ancient prophecy and the mark of the World Killer, Reign. Meanwhile, the tension…

Struggling to heal from her injuries inflicted by Reign, Supergirl remains in a dreamlike state, unable to be reached. Mon-El recruits one of the Legion members, Brainiac-5, to try to…