The Doctor takes Amy to the distant future, where she finds Britain in space. Starship UK houses the future of the British people, as they search the stars for a new home. But as Amy explores, she encounters the terrifying Smilers and learns a deadly truth inside the Voting Booth.
When Supergirl needs help, Alex asks Lena and Brainiac to team up. Meanwhile, J'onn questions his decision to quit the DEO. However, after running into Manchester Black (guest star DAVID AYALA), he realizes there are a lot of ways to help his fellow aliens during this tumultuous time.
James falls in deeper with the Children of Liberty in his efforts to meet Agent Liberty. Meanwhile, Supergirl and Manchester Black follow a lead on Agent Liberty's location, but things take a dark turn. Lena kicks off her first set of trials. Chad Lowe directs.
In the midseason finale, Nia has a powerful dream about Agent Liberty, but refuses to look at it as a prophetic dream and pushes it aside. After noticing something is bothering Nia, Kara enlists Brainy's help, and the two try to persuade Nia to embrace her destiny. Meanwhile, Manchester Black pays Ben Lockwood a menacing visit. Kevin Smith directs.
When Manchester Black breaks out of prison with the help of his new team, The Elite, who are set on punishing the anti-alien forces, Supergirl pulls double duty as she tries to apprehend Manchester Black and his team as well as dealing with a shocking new development with Ben Lockwood.
