Rosemary's was a women's dress shop which is a front for a secret FBI prison.
Peggy Carter came to Dottie Underwood's cell under the guise of Katherine Wexford, Underwood's psychiatrist. Alone, Underwood noted that Carter was showing signs of being in pain and stated she was in need of her help since the agent had come to her cell under a false identity. Carter admitted she had come to free Underwood for a mission and proceed to tell her she would handle the on-duty guard and once she was out that she needed to go the right. Before she left, Carter gave Underwood a magnet which was powerful to unlock her cell door.
After Peggy Carter left, Dottie Underwood used the magnet to unlock her cell door and escaped her cell. In the hall, she found the unconscious guard and hurried down the hall and out of the building. Once outside on the street, Underwood looked around and then headed to her right instead to the left as Carter had instructed. She turned down an alley beside the building and came face to face with a waiting Carter and Daniel Sousa. Underwood was then caught in a net fired from a net gun by Sousa and was incapacitated by an electrical shock by Carter.