Yelena Belova, code named Black Widow and known by her alias Dottie Underwood, is a Russian spy and assassin, hoping to fulfill the will of Leviathan and plunge all of New York City into chaos for the terrorist organization's plans.
She managed to escape custody, however was eventually captured by the SSR and spent several weeks into jail. Eventually breaking out, Yelena fled back to the U.S.S.R. to take over teaching at the Red Room, where, many years later into her old age and code named Madame B, she became the personal trainer to the second Black Widow Natasha Romanoff, keeping a close eye on her for HYDRA's plans to use her in the future.
- Master Acrobat: Belova is a highly skilled acrobat. She was able to jump against a wall to build up momentum and jump on top of Otto Mink to kill him, and landing skillfully once the attack had been completed. She used the railings and banisters of a staircase to jump down ten flights of a building to avoid capture from the SSR.
- Expert Martial Artist: Belova is highly trained in martial arts, combined with her acrobatic prowess, she was able to easily kill Otto Mink while he was pointing an Automatic Pistol at her. Her combat skills allowed her to disarm Carter and easily overpower her before she got kicked out of a window.
- Master Spy: Trained from childhood to be a spy, Belova convincingly assumed the guise of a harmless and slightly naive girl from Iowa, managing to fool even Peggy Carter, a trained intelligence agent. Aiding her in her deceptions is her ability to adopt various accents. Belova is able to fake multiple emotions and was able to seduce Howard Stark and sleep with him to learn of the locations of his weapons.
- Master Tactician: Belova is highly skilled in tactics, and was able to break in the room of Peggy without leaving any trails. She was even able to subdue Peggy using her own lipstick against her. Creating a distraction Underwood was able to abduct a heavily guarded Howard Stark.