Peggy is contacted by old acquaintance Howard Stark when he is framed for unleashing his deadliest weapons and can trust no one else. To help Peggy clear Stark's name, he insists his butler, Edwin Jarvis, be at her beck and call--whether she likes it or not. But the risk is great: If caught, Agent Carter could be targeted as a traitor and spend the rest of her days in prison... or worse.
In 1946, as Carter prepares to go to work for the New York City branch of the Strategic Scientific Reserve, her roommate, Colleen O'Brien, returns from her night work, relating stories of the return of the veterans and how they have replaced the more experienced women on the job. O'Brien believes that Carter works for the phone company because that is the front used by the spy agency.
Meanwhile, Howard Stark is robbed of many potent and dangerous inventions. The United States Congress have him in trials for three days, in an attempt to learn whether or not he was a traitor since some of his technology has been discovered being used overseas.
The SSR is put on the Stark case when he does not arrive for one of his hearings. Carter has been reading about this in the newspaper and knows Stark from the war, vouching that he is no traitor, but the agents belittle her viewpoint, even joking her about being Captain America's "liaison." Daniel Sousa defends Carter, but she disapproves, citing that she can defend herself.
After work, Carter eats dinner at the L&L Automat, an automat restaurant where her friend Angie Martinelli works as a waitress. She watches Martinelli deal with the harassment of a returned veteran, then finds a note on her table. This note leads her outside, where she meets Edwin Jarvis and Howard Stark. Stark is about to leave to go overseas to recover some of his missing technology, so he asks Carter to clear his name by finding his stolen tech in the United States. He specifically asks her to find a document with the formula for Nitramene, an incredibly powerful explosive. Stark explains that Jarvis, his butler, will offer her any assistance needed, though she insists that she does not need any.
Carter learns that the SSR plans to infiltrate La Martinique, a nightclub run by a fence called Spider Raymond; she dons a disguise and goes there on her own. While there, she seduces Raymond into revealing that he has the Nitramene, before knocking him out. Upon breaking into Raymond's safe, she finds an active Nitramene bomb. Taking the bomb home, Carter defuses it with Jarvis' help; however, when she emerges from the bathroom, she finds O'Brien dead and a Man in a Green Suit, who had killed Raymond, about to kill her. She fights with the assassin, burning his hand on the stove and causing him to flee, before she cries over her murdered friend.
Carter and Jarvis go visit Anton Vanko at the Stark Industries New York Facility, who tells them that Nitramene emits Vita Radiation and that only the Roxxon Corporation has the means of weaponizing the formula. She goes to the SSR file room and gets a Vita-Ray Detector from the Project Rebirth file box in order to help her locate Nitramene bombs.
Meanwhile, The Man in the Green Suit uses the Remote Typewriter to discuss the failure to apprehend the Nitramene bomb and blames Carter for the mishap, and receives instructions to do whatever is necessary, including terminating her.
Inside the Roxxon Refinery, Carter knocks one man out, and then confronts Leet Brannis, the man who sold Raymond the bomb; he has a milk truck loaded with bombs of the chemical. Carter sees the Y-shaped incision in his neck, and he speaks to her with the aid of a Voice Synthesizer. Brannis tells her that Leviathan will come soon, and releases one of the bombs, giving Carter thirty seconds to escape. She calls Jarvis to bring the car around, and the pair are just barely able to escape the explosion and subsequent implosion.
Jack Thompson, the lead investigator from the SSR, obtains a camera from the nightclub with a picture of a blonde who was spotted at the Raymond murder scene.
As the sun rises, Carter and Jarvis talk at L&L Automat, where she tells him about Brannis' cryptic "Leviathan" comment. As Jarvis leaves, she spots a veteran harassing Martinelli and threatens him enough for him to leave the waitress a good tip and to find a new place to eat. Outside, Jarvis makes a secret phone call to Howard Stark, telling Stark that Carter was a perfect choice and would have no suspicions at all.
- Hayley Atwell as Peggy Carter
- James D'Arcy as Edwin Jarvis
- Chad Michael Murray as Jack Thompson
- Enver Gjokaj as Daniel Sousa
- Shea Whigham as Roger Dooley
Special Guest Star:
- Lyndsy Fonseca as Angie Martinelli
- Kyle Bornheimer as Agent Ray Krzeminski
- Alexander Carroll as Agent Yauch
- James Frain as Leet Brannis
- James Hebert as Sasha Demidov
- Ashley Hinshaw as Colleen O'Brien
- James Urbaniak as Miles Van Ert
- Andre Royo as Spider Raymond
- Lesley Boone as Rose Roberts
- Bill Kalmenson as Senator Webster
- Costa Ronin as Doctor Anton Vanko
- Tim True as Tipsy Guy
- Jeffrey David Anderson as Short Bouncer
- Carrick O'Quinn as Tall Bouncer
- Kevin Heffernan as Madison Avenue Guy
- Johnny Marques as Bartender
- Rob Mars as Jerome Zandow (uncredited)
- Kirsten Vangsness as Ruby (uncredited)
- Kai Valerius as Businessman (uncredited)
- Chris Evans as Steve Rogers/Captain America (archive footage; uncredited)
- Unknown Actress as Ana Jarvis (uncredited)
- New York City, New York
- Washington, D.C. (footage)
- United States Capitol (footage)
- Passaic, New Jersey (mentioned)
- Iwo Jima, Japan (mentioned)
- Okinawa, Japan (mentioned)
- Monaco (mentioned)
- Guadalcanal, Solomon Islands (mentioned)
- London, England (mentioned)
- Germany (map)
- Ambush at Colleen O'Brien's Apartment
- Destruction of the Roxxon Refinery
- World War II (mentioned)
- Vita Radiation
- Sweet Dreams Lipstick
- Pick-Lock Wristwatch
- Vita-Ray Detector
- Stun Light Device
- Remote Typewriter
- Voice Synthesizer
- Daisy Clover Milk
- Captain America's Uniform (flashback)
- Strategic Scientific Reserve
- The New York Examiner
- Stark Industries
- Roxxon Corporation
- United States Congress
- Daisy Clover
- Lucky Star Cab Company
- United States Army
- United States Navy (mentioned)
- Franklin Chemical (mentioned)
- Eaglestar (mentioned)
- Red Skull
- Abraham Erskine
- Patrick O'Brien
- Franklin D. Roosevelt
- Winston Churchill
- Harry S. Truman (picture)
- Benny Goodman
- Daniel Sousa's Father
- B. Hornbuckle
- Sydney N. Bradley
- SM Mannion
- Jane Russell
- Is You Is or Is You Ain't
|That Man||Caro Emerald|
|Sugar (That Sugar Baby O'mine)||Jo Stafford|
|Spendin' All My Rainy Days With You||Glenn Crytzer's Savoy Seven||
- This episode was nominated for a Visual Effects Society Award for Outstanding Supporting Visual Effects in a Photoreal Episode.
- Now is Not the End was aired along with Bridge and Tunnel as part of a special 2-hour premiere.