Ryn discovers a refuge of injured mermaids that escaped Tia’s violent takeover. Ben and Xander get caught in a battle with Tia’s troops. Maddie feeds Robb half-truths to secure his…

The team races to stop Flynn before the bloody Battle of the Alamo ensues, but will it be victory or death for our time-traveling trio?

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.

With Ortega’s fate hanging in the balance, Kovacs drops a bombshell on the Bancrofts. Later, he comes face to face with an unsettling opponent.