Full story
Season 1 opens in 1946 New York. Peggy Carter is still grieving Steve Rogers and works at the Strategic Scientific Reserve, the SSR, where her male coworkers treat her like a secretary. Howard Stark is accused of selling dangerous weapons to the country's enemies and goes on the run. He secretly asks Peggy for help, and she starts investigating on the side, backed by Edwin Jarvis, Stark's butler.
The trail leads to nitramene bombs, a Roxxon refinery, and a mysterious Russian group called Leviathan. Worse, one of the items stolen from Stark is a sample of Steve's blood. Peggy hides everything from the SSR, and Agent Daniel Sousa starts to suspect her. Her friendly neighbor Dottie Underwood turns out to be a killer trained in a Soviet program that turned young girls into operatives. Dr. Ivchenko, rescued from Russia by the SSR, is actually a hypnotist working for Leviathan. He takes control of Chief Dooley, who dies sacrificing himself, and releases a gas that drives people to violence, causing a massacre in a movie theater. The endgame is to use Stark to drop the gas over Times Square. Peggy takes down Dottie, Sousa arrests Ivchenko, and the attack is stopped. Cleared at last, Peggy pours Steve's blood into the river and moves on. Ivchenko lands in a cell next to Arnim Zola, a nod to Hydra.
Season 2 takes Peggy to Los Angeles in 1947 to help Sousa, now head of the local SSR office. A frozen body turns up in a lake in the middle of a heat wave. The case leads to Isodyne Energy and Zero Matter, a substance from another dimension. The villain is Whitney Frost, a brilliant, ambitious actress married to Isodyne's owner. When she absorbs Zero Matter, she gains powers and starts swallowing people whole. Scientist Jason Wilkes, Peggy's ally and love interest, becomes invisible and loses his body.
Frost takes over the Council of Nine, a secret group pulling the country's strings, and kidnaps Wilkes. Jarvis and his wife, Ana, pay a heavy price: Ana is shot and can no longer have children. In the final showdown, the team opens a dimensional rift, pulls the Zero Matter out of Frost, and leaves her broken and committed to an asylum. Wilkes recovers. Jack Thompson tries to betray the group and fails. Peggy decides to stay in Los Angeles and kisses Sousa. The last hook is left hanging: Thompson is shot in his hotel room and someone steals a file on Peggy.