Kelly Reilly was born on July 18, 1977, in Chessington, Surrey, England12. She grew up in a working-class family, with her mother working as a hospital receptionist and her father, Jack Reilly, serving as a police officer13. Reilly attended Tolworth Girls' School in Kingston, where she initially struggled academically and felt uncomfortable in her own skin3.

Despite her early challenges, Reilly's life took a turn when she discovered her passion for acting at age 14, thanks to two drama teachers who introduced her to theatre2. This newfound interest provided an outlet for the naturally shy child, who had previously withdrawn into herself3. At 16, Reilly performed a monologue during an actor's showcase, catching the attention of a casting director and leading to her first professional role2. Her determination to pursue acting was evident early on, as she began bombarding the casting director of "Prime Suspect" with letters requesting auditions, despite her parents' initial reservations about her chosen career path3.

Kelly Reilly's breakthrough role came in the acclaimed British crime drama series "Prime Suspect" starring Helen Mirren. At just 16 years old, Reilly took the initiative to write to the show's producers asking for work12. Her determination paid off when she was cast in "Prime Suspect 4: Inner Circle," which aired on ITV in 19952. This early appearance alongside the legendary Helen Mirren marked the beginning of Reilly's professional acting career and set the stage for her future success.

• Reilly played the daughter of a prime suspect in the series3

• The role came after she performed a monologue at an actor's showcase, catching the attention of a casting director4

• This early exposure to high-caliber television production and acting talent proved invaluable for Reilly's development as an actress

Kelly Reilly's stage career reached new heights with her performance in Patrick Marber's adaptation of "After Miss Julie" at the Donmar Warehouse in 2003. Her portrayal of the titular character earned her widespread critical acclaim and a nomination for the Laurence Olivier Theatre Award for Best Actress12. At just 26 years old, Reilly became the youngest person ever nominated for this prestigious award3.

The production, directed by Michael Grandage, showcased Reilly's ability to inhabit complex characters with depth and nuance. Her performance was described as "sensually neurotic" and "utterly instinctual"2. This role not only solidified Reilly's reputation as a formidable stage actress but also opened doors for her in both theater and film, leading to a series of carefully chosen roles that would further establish her as one of Britain's most talented performers12.