After Supergirl defeated Queen Rhea and her Daxamite army at the end of the second season, the third season focused on Kara Danvers having to battle against Kryptonian worldkiller known as Reign, who was also transported to Earth just before Krypton’s destruction. Living out her life as Samantha Arias, she remained unaware of her origins until her powers started to manifest, then becoming Supergirl’s biggest adversary. The fourth season will see Kara having to take on Agent Liberty.
Jon Cryer will debut in the fifteen episode of the season titled O Brother, Where Art Thou? and here is a brief synopsis of the episode below:
Lex Luthor reaches out from prison to enlist Lena into one of his plans and will stop at nothing to get her on board, even if that means leveraging the life of one of her friends.
The fourth season also stars Melissa Benoist, Mehcad Brooks, Chyler Leigh, Jesse Rath, David Harewood, Katie McGrath, Jeremy Jordan, Sam Witwer, Nicole Maines, April Parker Jones, David Ajala, Rhona Mitra, Robert Baker, Bruce Boxleitner, Anthony Konechny, Azie Tesfai, Hannah James, Kate Burton and Jessica Meraz.