help me find this book!

okay so I read this book like 2 years ago and it was my favorite Bucky Barnes book.
I distinctly remember the main character being a girl and she was an assassin. The opening scene was her at a ball of some sorts with a Target and the team including everyone in the avengers were on a mission to try and stop her but she ended up killing her target anyway in the back room. I remember she was like a super big feminist. One distinct thing I remember in the story was that she later found out that her dad was working with Hydra and she thought he was a dentist. HELP ME FIND IT PLEASEEEEE