Shauna Macdonald is a Scottish actress. She began her career starring in The Debt Collector. She then had her breakthrough starring as Sam Buxton in the television series Spooks. After departing the series, she starred as Sarah Carter in the horror film The Descent, the role for which she is best known. She gained widespread recognition and praise for her performance, and was nominated for the Saturn Award for Best Actress. The film established Macdonald as a scream queen.