Kara attempts to mend her relationship with Lena, J'onn J'onzz takes a deep dive into his memories, and Kelly tries to help an old friend.
Supergirl, Alex and Brainiac thwart an alien attack while William investigates Kara; J'onn J'onzz and Kelly use Obsidian tech to solve a problem.
Secretly furloughed from prison due to failing health, Lex Luthor visits his sister to seek her help; Lena is suspicious of Lex's motives, but when she's faced with a life and death situation, she must decide how she truly feels about her brother.
Kara and Lena team up and visit Stryker's Island to search for intel to take down Lex. Kara attempts to befriend a prisoner who may know what Lex was up to, while Lena investigates puzzles Lex left behind.
