Rosamund Mary Ellen Pike (born 1979) is an English actress and producer. Known for her portrayals of complex and morally ambiguous women in psychological thrillers, her accolades include a Primetime Emmy Award and a Golden Globe, in addition to nominations for an Academy Award and two British Academy Awards.

A graduate of Wadham College, Oxford, Pike drew early recognition from her work in stage productions, including Romeo and Juliet at the National Youth Theatre, before her professional debut as Bond girl Miranda Frost in Die Another Day (2002). Supporting roles in the period dramas Pride & Prejudice (2005), An Education (2009) and Made in Dagenham (2010) were followed by further mainstream film credits including Johnny English Reborn (2011), Wrath of the Titans (2012), Jack Reacher (2012) and The World's End (2013). For her portrayal of Amy Dunne in the psychological thriller Gone Girl (2014), Pike earned a nomination for the Academy Award for Best Actress.

Pike's career further progressed with her portrayals of Ruth Williams Khama in the biopic A United Kingdom (2016) and Marie Colvin in the war film A Private War (2018), and she won the Golden Globe Award for Best Actress for her leading role in the black comedy I Care a Lot (2020). During this period, she won the Primetime Emmy Award for Outstanding Actress for her role in the comedy miniseries State of the Union (2019). After starring as Moiraine Damodred in the Amazon Prime Video fantasy series The Wheel of Time, she received renewed acclaim and awards nominations for her performance in the satirical thriller Saltburn (2023). For producing the Netflix science fiction series 3 Body Problem (2024), Pike earned a nomination for the Primetime Emmy Award for Outstanding Drama Series. In 2025, she returned to the stage for the first time in 15 years with her performance in the Royal National Theatre production Inter Alia.