“In Search of Lost Time” is episode fifteen of season three of Supergirl.
Lena is with an unconscious Sam in the facility seen in the previous episode, “Schott Through the Heart”. Lena has run tests and confirmed Sam is transforming. She’s in a medically induced coma but Lena needs her awake now. She’s going to end the sedation. And hopes it’s Sam who wakes up.
Everyone is at Kara’s and J’onn talks to Kara about M’yrnn’s illness. M’yrnn mentions how J’onn used to move pieces in a game when he was young and blame his imaginary friend. Alex gets a message about a disturbance down town. Kara starts unbuttoning her shirt, not ripping it off. When everyone looks at her, she says she likes the shirt. The disturbance is at the alien bar and Supergirl has to take down an alien who has gone off on one.
The alien is brought back to the DEO and Kara, Alex and J’onn are with her. She’s a Kalanorian with no criminal record. According to J’onn, they are psychics and empaths, prone to outbursts during astronomical events. J’onn is more concerned about the Worldkillers.
Mon-El and Winn say there’s been no sign of Reign or Purity since the subway. Given their experience of the Blight in the future, Pestilence is easy to see coming. Diseases, plagues, Old Testament stuff. And there’s a river of blood in the arctic which Imra and Brainy have gone to check out. Kara, in the meantime, wants Mon-El to train her to fight like they do in the future.
Sam wakes and asks what’s wrong with her. Lena explains she’s changing at a cellular level. To Reign. Sam doesn’t believe this. Lena also has a timeline of Reign’s appearances and Sam’s blackouts. They match. Sam still doesn’t believe her and wants to go be with Ruby. Except she’s imprisoned behind a forcefield. Lena says Sam asked her to help.
Kara and Mon-El are looking at a hologram of Reign and analysing how she fights. Mon-El says that the cape comes in as Kara needs to be like a bullfighter. Winn enters; he’s done something amazing. Well, okay. Fixed Mon-El’s old suit.
J’onn arrives at home where M’yrnn is playing a game to help with his mind. J’onn mentions bringing in a Kalanorian who had a psychic breakdown in a bar. It sounds like that was caused by M’yrnn; he should have been told there were Kalanorians present. M’yrnn wants to play a game but J’onn has to get back to work. Bring it with them to the DEO and they can play later. M’yrnn first needs to finish playing with J’onn’s imaginary friend. He’s winding J’onn up.
Sam is asking Lena how she thinks Sam could have killed all those people. Lena doesn’t. But Reign is a separate entity. Sam isn’t buying it, then Lena gets a call. It’s about James, who’s at Lena’s office. Lena heads to see him and talks about an employee having a health problem but they won’t accept it. James tells her that sometimes all you can do is hold a mirror up.
Mon-El and Supergirl are training as J’onn and M’yrnn arrive at the DEO. M’yrnn heads to pray, but as he’s doing so, Winn gets into an almost fatal argument with Demos and Kara starts losing control of her anger. M’yrnn is having an effect on everyone, and he’s getting worse. Though both Alex and Mon-El wonder if Kara’s anger is coming from other issues as well. Lena is also trying to convince Sam she’s Reign.