In Pennsylvania, two scout leaders tell ghost stories to the boy scouts. One of the leaders hears a humming and goes off to investigate. He starts screaming and the others run to the car. Before they can get away an electric jolt shoots out the car's battery. The scouts emerge to find their leader dead, suspended in midair.
Coulson takes his yearly physical early saying that his therapist requested it. Grant is unhappy with Fitz's dendrotoxin gun because it is an ounce too heavy. After he leaves the room, Fitz mocks him. Simmons even partakes in the mocking. The agents investigate the victim who is still suspended in air. He is still there until Jemma steps closer and is shocked by a static shock.
Skye investigates everything about the victim but finds nothing suspicious. Coulson scolds Grant for being too hard on Skye. May interrogates the other scout leader, while Simmons autopsies the dead body. Fitz doesn't even want to be in the lab with the corpse. She is incredibly intrigued by his head wound. Fitz discovers another electrostatic event at a nearby farm. Coulson, Grant, and May rush off to investigate but on the way Fitz loses all readings of the energy. They enter the barn and find the victim in the same manner as the first, suspended in midair. Skye finds out that the thing in common between the two victims is that they both volunteer at the same local fire station.
In a cutaway scene, an unknown man sets a helmet on a shelf. The helmet pulses with electricity.
Fitz's robot drone flies up to the body and after it is shocked they both fall down. Skye finds out that the victims were dispatched to aid during the battle for New York. Jemma is curious to discover that the head wounds on the bodies are exit wounds. She discovers that it is inside the victims.
Coulson, May, and Grant head to the fire station. Coulson tells them of their new loss but one fire fighter, the unknown man from before, is visually distraught.
Skye notices a new signal coming from the fire station. Coulson confronts the fire fighter, who begins hearing a humming noise. May discovers a Chitauri helmet. The truth, that the three fire fighters contracted an alien virus from the souvenir helmet, is revealed and, though Coulson tries to comfort him about dying, the fire fighter faces the same fate.
The agents send the fire fighters to be quaranteened and take the helmet onto the Bus for transport to the Sandbox.
May confronts Coulson about his physical and asks that he would tell her if something was wrong. Simmons makes a breakthrough that the virus was spread from the helmet to the fire fighters by static shock. As she is explaining it to Coulson, a metal lab utensil begins hovering. He locks her into the lab realizing that she has contracted the virus.
Simmons despairs believing that she only has about two hours. Fitz delivers everything that she needs through a slide in the lab's wall. She begins testing on three lab rats but the first two are failures.
Skye walks in on Grant watching the lab security cameras. He expresses that he wishes there was actually something physical he could fight as this is his strong point. He says all they can do is wait on whatever it is they are called on to do.
Coulson talks to Agent Blake over video phone. His superior orders him to dump infected cargo into the ocean but he hangs up claiming he has a bad connection.
Skye frantically works on the antiserum to save herself and as she argues with Fitz she realizes that they need the antibodies found in the helmet. Fitz retrieves the helmet and goes into the unlocked lab to help her. They test on the third rat but it is presumed dead. Jemma asks for a moment alone with Fitz but she knocks him out and leaves the lab... to jump from the plane. Fitz realizes the rat was just knocked out by the jolt of electricity just too late to stop her from jumping.
Grant hurriedly straps on a parachute and dives out after her. He is able to save her and bring her back onto the plane where Coulson scolds her for her stunt but says gently that he they don't want to lose her. Grant compliments her bravery but then reveals that he knew the scientists had been mocking him. Skye hugs Simmons.
Coulson tells May that his doctors weren't the ones who required his tests; he wanted them. He says the results say he is fine but he feels different. She asks to see the scar under his shirt and she tells him that he died and there is no way to come out of it unchanged and that it is to remind him to only move forward.
Simmons thanks Fitz for being by her side the whole time and she kisses his cheek.
At the Sandbox, Agent Blake reprimands Coulson for disobeying his orders. He notes that Coulson is not the same and as he exits the bus he runs a finger down the side of Lola.