Byrne was born in Sydney, Australia, in 1979. She began acting at a young age, and by her early 20s, she had already starred in several Australian films and television shows. In 2002, she made her Hollywood debut in the horror film "28 Days Later." Since then, she has appeared in a variety of films, including "Troy," "Sunshine," "X-Men: First Class," and "Neighbors."
But it was her role as Helen Harris in the 2011 comedy "Bridesmaids" that truly launched Byrne's career in Hollywood. Her performance as the uptight and controlling maid of honor was both hilarious and heartbreaking, and it earned her a Golden Globe nomination for Best Supporting Actress.
Since "Bridesmaids," Byrne has continued to impress critics and audiences alike with her work in films such as "Insidious," "Annie," and "Star Wars: Episode VII - The Force Awakens." She has also had memorable roles in television shows such as "Damages" and "Mrs. America."
One of the things that makes Byrne such a compelling actress is her ability to play both comedy and drama with equal ease. She can be both funny and heartbreaking, and she always manages to find the truth in her characters. As a result, she is one of the most versatile and talented actresses working in Hollywood today.