In 1946, Peggy Carter, mourning the apparent death of her lover Steve Rogers, returns to work for the Strategic Science Reserve in New York City. The S.S.R. investigates industrialist Howard Stark, who has disappeared, for apparently selling weapons to US enemies. Stark secretly reaches out to Carter, and asks her to help him clear his name. Before he leaves, he tells her about his formula for molecular nitramene that is going to be sold at a club. Infiltrating the club in disguise, Carter learns that the formula has been weaponized. Carter shows a nitramene bomb to Stark Industries scientist Anton Vanko, who deduces that it came from a Roxxon Oil refinery. Carter and Stark's butler, Edwin Jarvis, investigate the refinery, where they encounter Leet Brannis. Brannis, who works for "Leviathan", escapes with a truck full of the nitramene weapons. Before leaving, Brannis drops a weapon that destroys the entire building as Carter and Jarvis escape.