Rosamund Mary Ellen Pike (born 1979) is an English actress and producer. Known for her portrayals of morally ambiguous women in psychological thrillers and dramas, she is the recipient of numerous accolades, including a Primetime Emmy Award and a Golden Globe Award, as well as nominations for an Academy Award and two BAFTA Awards.

Pike studied at Wadham College, Oxford, and appeared in stage productions, including Romeo and Juliet at the National Youth Theatre, before beginning her acting career. She had her breakthrough for her film debut as Bond girl Miranda Frost in Die Another Day (2002), and had supporting roles in the period dramas Pride & Prejudice (2005), An Education (2009) and Made in Dagenham (2010).

In the next decade, Pike had mainstream film appearances in Johnny English Reborn (2011), Wrath of the Titans (2012), Jack Reacher (2012) and The World's End (2013). She received acclaim for her starring role as Amy Dunne in the psychological thriller Gone Girl (2014), which earned her nominations for the Golden Globe Award, British Academy Film Award, and Academy Award for Best Actress. Pike then portrayed Ruth Williams Khama in the biopic A United Kingdom (2016) and Marie Colvin in the war film A Private War (2018), for which she received her second Golden Globe Award nomination. She won her first Golden Globe Award for her leading performance in the dark comedy film I Care a Lot (2020), while her supporting role in the black comedy Saltburn (2023) earned her additional nominations from the Golden Globe and BAFTA Awards.

On television, Pike won a Primetime Emmy Award for her role in the comedy miniseries State of the Union (2019). In 2021, she began starring as Moiraine Damodred in the Amazon Prime Video fantasy series The Wheel of Time, and in 2024, she was nominated for the Primetime Emmy Award for Outstanding Drama Series as an executive producer of the science fiction series 3 Body Problem.