Mary Elizabeth Winstead (born November 28, 1984) is an American actress and singer. Her first major role was that of Jessica Bennett on the NBC soap opera Passions (1999–2000). She came to wider attention for her roles in the horror series Wolf Lake (2001–2002), the horror films Final Destination 3 (2006) and Death Proof (2007), and the slasher film Black Christmas (2006); by the end of the 2000s she had gained a reputation as a scream queen.

Further success came with her roles as John McClane's daughter in Live Free or Die Hard (2007) and Ramona Flowers in Scott Pilgrim vs. the World (2010). Her critically acclaimed performance as an alcoholic struggling with sobriety in the drama Smashed (2012) was followed by a series of roles in other independent films, including The Beauty Inside (2012), The Spectacular Now (2013), Faults (2014), Alex of Venice (2014), and Swiss Army Man (2016). Winstead had further horror film roles in The Thing (2011), Abraham Lincoln: Vampire Hunter (2012), and 10 Cloverfield Lane (2016). Since 2013, Winstead has performed as music duo Got a Girl with Dan the Automator.

Winstead returned to television with the drama series The Returned (2015), the comedy series BrainDead (2016), the medical drama series Mercy Street (2016–17), and the third season of the crime drama Fargo (2017). Her other roles include the comedy-drama All About Nina (2018), the action film Gemini Man (2019), the Huntress in Birds of Prey (2020), and Hera Syndulla in the Star Wars series Ahsoka (2023).