Rosamund Mary Ellen Pike (born January 27, 1979) is a British actress. She has received various accolades, including a Golden Globe Award and a Primetime Emmy Award, in addition to nominations for an Academy Award and a British Academy Film Award.

Pike began her acting career by appearing in stage productions such as Romeo and Juliet, alongside Paul Ready, and Gas Light. After her screen debut in the television film A Rather English Marriage (1998) and television roles in Wives and Daughters (1999) and Love in a Cold Climate (2001), she received international recognition for her film debut as Bond girl Miranda Frost in Die Another Day (2002), for which she received the Empire Award for Best Newcomer. Following her breakthrough, she won the BIFA Award for Best Supporting Actress for The Libertine (2004) and portrayed Jane Bennet in Pride & Prejudice (2005).

Pike had film appearances in the sci-fi film Doom (2005), the crime-mystery thriller film Fracture (2007), the drama film Fugitive Pieces (2007), the coming-of-age drama An Education (2009), for which she was nominated for the London Film Critics' Circle Award for British Supporting Actress of the Year, and sci-fi comedy The World's End (2013). She also received British Independent Film Award nominations for An Education and Made in Dagenham (2010), and was nominated for a Genie Award for Barney's Version (2010). Her other films include the spy action comedy Johnny English Reborn (2011), the epic action-adventure fantasy Wrath of the Titans (2012), and the action thriller Jack Reacher (2012).

In 2014, her performance in the psychological thriller Gone Girl was met with widespread critical acclaim, winning the Saturn Award for Best Actress and receiving a nomination for the Academy Award for Best Actress. Pike received further acclaim for her starring role as Ruth Williams Khama in the biographical drama A United Kingdom (2016) and for portraying the journalist Marie Colvin in the biographical war drama A Private War (2018), for which she was nominated for the Golden Globe Award for Best Actress in a Motion Picture – Drama. Pike won a Primetime Emmy Award for her role in State of the Union in 2019. She won a Golden Globe Award for her performance in I Care a Lot (2020). She has also starred in the Amazon Original series The Wheel of Time (2021–present).