Dafne Keen as Negasonic Teenage Warhead - Deadpool: The One and Only Origin Fan Cast | myCast.io
Dafne Keen
Age: 21
female
Dafne Keen Fernández (born 4 January 2005) is a Spanish and British actress. Keen made her child acting debut in the series The Refugees (2015). Her breakthrough role was as Laura in the X-Men superhero film Logan (2017), which she reprised for the Marvel Cinematic Universe (MCU) film Deadpool & Wolverine (2024). She also starred as Lyra Belacqua in the television series His Dark Materials (2019–2022) and Jecki Lon in the Star Wars series The Acolyte (2024).
Description above from the Wikipedia article Dafne Keen, licensed under CC-BY-SA, full list of contributors on Wikipedia.
When a wisecracking mercenary gets experimented on, he gains immortality, gets disfigured as a result, and escapes his captors. After a few months are spent in hiding, he decides to kill the people responsible for ruining his good looks.