Lena is doing tests on Sam, who has been in a medically induced coma for three days. 

The gang has game night at Kara's until Kara has to leave to fight an alien at the bar. She brings her back to the DEO unconscious. 

Sam wakes up and Lena tells her that she changes into Reign when she blacks out. Sam is in disbelief and tries to leave, but Lena won't let her.

Mon-El teaches Kara fighting techniques of the future to help her defeat Reign.

M'yrnn's psychic abilities start to affect those in the DEO. Winn and another agent start fighting and Winn pulls a gun on him. Alex breaks it up and then she and Winn begin fighting until Kara pulls them apart. J'onn puts up a barrier to protect everyone. 

Kara and Alex check on the alien from the bar. She's seizing and speaking Martian. 

Lena goads Sam until she loses control and Reign emerges. She records it and shows it to Sam, who is devastated by what she has done.

Another episode occurs, but this time Alex, Kara, and Winn have inhibitors to protect them. Mon-El is protected by his Legion ring. J'onn tries to get through to his father. He has to use special technology to protect him and everyone else.