Dottie was raised and trained in Red Room Academy to be an assassin. One day during training she had to kill her best friend Anya by order of her teacher.
Dottie Underwood is the new tenant of Griffith Hotel after Molly Boldwen is kicked out by Miriam Fry. As Underwood appeared as a ballerina, Ms. Fry immediately accepts because she loves ballet. Later, she meets Angie and Peggy Carter who will be their new neighbors.
When Zandow was arrested by the SSR, Underwood follows Ray Krzeminski, who was carrying Zandow to the New York Bell Company. Underwood then hits him hard against Krzeminski's car. Krzeminski goes out only to be killed by the Soviet assassin. Seeing what happened, Zandow pleads for his life but Underwood ignores his begs and quickly kills him. Underwood leave the scene after the success of her mission.
Dottie with the other tenants of the Griffith Hotel discussed different methods to transport food to the room. She then asks a neighbor if he could create one for her, to which Gloria accepts. Later, she found Otto Mink trying to enter the room of Peggy. Mink orders her to return to her room. Seeing that Mink had an automatic pistol, Underwood attacks him because she wanted it for her. While she watched with the automatic pistol Angie knocks on her door to come down to dinner.
Dottie asked Peggy to give him a tour of New York because she did not know the city, Peggy accepts the request of her new friend. After the tour, Peggy and Dottie lunch at L & L Automat. Dottie "unintentionally" hits Carter's purse; its contents spill to the floor (it was only a plan to get the key of Peggy's room). That same night, Dottie entered to Peggy's room, and discover what she had already suspected (that Peggy Carter was helping Howard Stark).
Underwood went to a dentist's office that was in front of the New York Bell Company. After killing the dentist, Underwood and Ivchenko exchanged messages. Ivchenko told her that he needed more time to complete his mission. When Peggy was preparing to leave the hotel, she ambushes her and tells her that some agents were looking for her. Suddenly, Underwood kisses Carter with the purpose to make her unconscious.
When she was about to kill Carter; Thompson and Sousa arrived and saw Peggy passed out on the floor. Underwood told them that she does not know what happened to Carter. Later, she saw as Carter was taken into custody by the SSR.
Underwood leaves the Griffith Hotel and went to buy a baby carriage. She then returned to the dentist's office where Ivchenko told her that she need to prepared for an evacuation. Leaving the office, she was faced with Agent Sousa. Underwood manages to escape from Sousa and others SSR agents. She acquired a car and met with Ivchenko who carried Item 17. Ivchenko told her that Item 17 should be tested before its final use. Underwood entered a cinema room and activated Item 17, causing the audience to kill each other.
Underwood and Ivchenko drove as they discussed what to do with the Midnight Oil. Suddenly, a police officer stopped them by a traffic light have passed, but using her innocent persona she was able to convince the officer. When the officer was about to leave, he received a call describing Underwood and the car perfectly; the officer turned and watched as Underwood was pointing at him with a gun. Ivchenko and Underwood went to a warehouse of Howard Stark and she quickly killed an employee who tried to stop them. Ivchenko told her that they should return to the city after learning of the return of Howard Stark. Later, Underwood tied Stark to a chair and beat him so he could remember her name (something that would happen later). She flees after being beaten by Peggy Carter.
- Leviathan - Allies.
- Johann Fennhoff - Ally.
- Angie Martinelli - Neighbor.
- Howard Stark - Target.
- Peggy Carter - Target.
- Jerome Zandow - Victim.
- Ray Krzeminski - Victim.
- Otto Mink - Victim.
- As a blonde member of the Red Room and a dedicated Soviet Assassin, Dottie bears some similarities to the Marvel Comics character Yelena Belova, who within the comics continuity is a second, more villainous Black Widow and a bitter rival of the original. However, this character has not yet been depicted in the Marvel Cinematic Universe, nor any television adaptation to date.
- She also resembles The Joker from DC Comics in various ways:
- Both are openly sadistic and homicidal sociopaths who delight in violence, killing, and the causing of pain (with the exception of their own).
- Both speak in a deceptively friendly and cheerful tone despite their vicious dispositions and treat their actions like a humorous affair.
- Both are dangerously resourceful killers in spite of not having any clear superhuman powers.
- Both are violently obsessed with the hero who opposes them (Agent Carter and Batman, respectively), and seem legitimately fascinated by them whilst also desiring their violent deaths.
- Both are also villains that the hero has gone out of their way to save from certain death to the incredulity of other characters who argue that the hero should just allow them to die.
- Both have consistently avoided facing long-term punishment for their crimes (as Joker regularly escapes from Arkham Asylum and Dottie Underwood from SSR custody).
- Both are known only by their aliases (Dottie Underwood and Joker), their real names being unknown.