Simmons becomes infected with an alien virus after exposing herself to a group of people that have come into contact with a Chitauri helmet.
- At the start of the episode Agent Coulson is taking his physical exam. In the lab Agent Ward is testing out a new weapon and says its an ounce too heavy. Once Ward leaves, Skye, Fitz and Simmons are making fun of him by doing impressions of him. Then Agent Coulson and the team investigate a series of deaths, involving levitation and electrostatic anomalies. Although the team initially assumed the deaths were caused by some form of weapon, the cause of the anomalies is discovered to be an alien virus found on a Chitauri helmet salvaged from the Battle of New York that turns the unwitting victims into electrostatic bombs.
When Agent Simmons is infected by the fatal virus, she and Agent Fitz work feverishly on a cure, while Coulson ignores a direct order to sacrifice Simmons to save the rest of the team. With time running out and unaware their last attempt was actually successful, Simmons knocks out Fitz to leap from the plane, but Ward manages to save her before she plunges to her death. Simmons then receives a telling off from Agent Coulson. Once outside his office, Ward mimics Skye, Fitz and Simmons' impressions of him that he overheard. After his physical reveals nothing unusual, Coulson confides in Agent May he is searching for some explanation for why he feels different. She points out that it would be impossible not to be changed by his seeming death; alluding to having gone through her own life-shattering incident. In the final scene, the helmet is delivered to the S.H.I.E.L.D. Sandbox facility to the possession of Agent Blake, who warns Coulson of the consequences of disobeying a direct order from headquarters.
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