Dr, Rosen is forced to challenge his most cherished values when he encounters an alpha leading a personality cult who sincerely wants to create a paradise for all humanity, a dream his alpha ability may make possible. But as members of the alpha group fall under the cult leaders and he refuses to recognize he may be responsible for the illnesses among the cult members Dr. Rosen is forced to act... if he can.
- TENNESSEE, 1980
A church where a mass suicide ritual is about to begin. Several bodies lie in the aisle. A leader of some sort speaks to a young boy about what is about to happen and knocks a can of gasoline over. Just as he lights the liquid on fire, the boy, Jonas, heads for the exit.
In present day, Dr. Rosen (David Strathairn) has Nina (Laura Mennell) give away her belongings to make a clean break from her past. Bill (Malik Yoba) pushes for the team to participate in a training program related to police tactics. Rosen doesn't like it, saying by choice he's never fired a gun. Hicks (Warren Christie) tells Rosen his wife is taking their child to another part of the country. He apparently got the shaft during custody hearings because of his past with alcohol. He looks longingly at a bottle of booze and then tells Rosen he's going to an AA meeting. Rachel (Azita Ghanizada) is desperate to bring a date to a family function so her parents won't try and set her up. It's looking like Gary (Ryan Cartwright) is her only option.
Hicks' AA meeting. A man addresses the group, saying he's not an alcoholic. Jonas (Garrett Dilahunt) thinks he's able to bring them happiness. Jonas begins to chant in a foreign dialogue. A white glow emanates from his body. Everybody in the room, including Hicks, seems to be pulled into some kind of spell.
At the gathering, Rachel hears everybody making fun of her for being with someone so young. When her father coughs, she is able to sense he is very sick and needs to go the doctor immediately. Instead, her parents yell at her for taking attention away from her sister during her engagement party.
Hicks and Nina start kissing. He says he's finally figured something out and wants her to come with him. They travel to an estate where Jonas is preparing to speak to a gathering of thousands. Nina looks around at everybody. She is immediately uncomfortable and wants to leave. When Jonas arrives, a man grabs her and immediately puts her under the same trance.
Rachel tries to explain to Gary why her father won't seek medical attention. He says she has to keep telling her father the truth until he gets it. With tears in her eyes, she agrees.
Hicks and Nina garden on Jonas' estate. They look into each other's eyes and strip off each other's clothes. As they make love, a man on the grounds clutches his chest. He starts seizing and drops to the ground. Nina and Hicks tell Jonas they must get the man to a doctor. They convince Jonas that Rosen would understand.
Rosen arrives at Jonas' compound. He finds a boy who tells him Jonas is "everybody's father." Jonas takes Rosen to his "patients," a room full of people lying in cots. Several need hospital care. At least one is dead. Jonas tells Rosen he helps people see the connection of all things. Rosen realizes he is an Alpha.
Jonas takes Rosen to see Hicks and Nina, who are in bed together. They defend Jonas' "gift." Cellular signals are blocked so Rosen can't contact the outside world.
Rosen tells Jonas his followers are suffering from Encephalitis Lethargica, a disease of the brain. He explains the neurological cause for what the people experience. Rosen continues to convince Jonas not to use his power on him, but tells him he needs to get the people some medicine. Jonas wants him to write a prescription and have somebody else pick up the drugs.
Rachel goes to see her father. She tells him he has cancer in his throat and if he doesn't see a doctor he will die. She tells him if he doesn't see a doctor the following day, she'll come back.
Rosen finds his car has been tampered with. Rosen watches Jonas say a few words before another of his followers is cremated. He tells Rosen this is how things have always been. It is up to him to change what happens.
Rachel and Gary come to the office. Bill tells them Rosen still hasn't show up. They realize Nina and Hicks are also missing. Gary can't ping any of them, meaning they aren't near a cell tower.
Rosen is finding the L-DOPA isn't helping Jonas' followers. Jonas tells him ever since he was young, people he's "gifted" have gotten sick. His father believed what happened was the darkness trying to steal back Jonas' gift and responded by purifying the congregation with fire. At least one member of the congregation has gotten better.
When the man recovers, he tells Jonas whatever he did to him felt like a drug to which he could easily become addicted. Jonas leaves. The man tells Rosen he wants to go home.
Gary figures out Rosen is probably at Jonas' house.
Rosen finds Jonas has taken away the L-DOPA because it is robbing his followers of his gift. Jonas tells him the worst part of his gift is he can't experience it himself. He tells Rosen he must find another answer.
Bill, Rachel and Gary arrive at the Jonas compound. Bill goes in alone, insisting the other two wait behind in the car. Nina spots Bill and uses her power to get Bill to give her his gun.
Rachel and Gary call for DOD backup. Gary wants them to go in after him. Rachel says no.
Inside the home Bill tells Jonas what to expect in terms of the forces coming.
Jonas tells Rosen he was a mistake. Josen never should have brought Rosen here. Rosen tells him again his "gift" is killing these people. He says he finally understands what his father was taking about. They will all burn.
We see Bill pouring gasoline around the home. He seems unable to use his alpha power. While Hicks pours gasoline, he falls to the ground in pain. Jonas tells Nina that Hicks has "been called."
Rosen breaks into Jonas' desk to get the medicine. He finds a handgun in there as well.
Jonas speaks to his followers while Rosen sneaks around giving people injections of medicine. Nina snaps out of it.She starts to help Rosen. Jonas begins to glow. Rosen sees what he is doing. Rosen shoots Jonas in the face. Jonas drops his torch to the floor. The house begins to burn.
Everybody manages to get out. Rachel tells a shaken Rosen that Jonas' victims are all responding.
Rachel's dad tells her his cancer should be treatable, since it is rarely caught so early.
Hicks and Nina agree not to talk about what happened between them to the rest of the group.
Rosen asks Bill (who still can't use his power) how the light felt. Rosen seems to feel like he should pay a price. Bill tells Rosen to aim for the chest next time. Rosen says that he was aiming for the chest!