Isla Lang Fisher (/ˈaɪlə/; born 3 February 1976) is an Australian actress and author. Born to Scottish parents in Oman, Fisher moved to Australia at age six where she began appearing in television commercials. She came to prominence for her portrayal of Shannon Reed on the Australian soap opera Home and Away from 1994 to 1997, for which she received two Logie Award nominations.
After various appearances on television and stage, Fisher made a successful transition to Hollywood with her portrayal of Mary Jane in the 2002 live-action adaptation of Scooby-Doo, and has since played prominent roles in films such as Wedding Crashers (2005), Confessions of a Shopaholic (2009), Bachelorette (2012), The Great Gatsby, Now You See Me (both 2013), and Nocturnal Animals (2016). Her other notable credits include Swimming Pool (2001), I Heart Huckabees (2004), London (2005), Wedding Daze (2006), The Lookout, Hot Rod (both 2007), Definitely, Maybe (2008), Burke & Hare (2010), Visions (2015), Grimsby, Keeping Up with the Joneses (both 2016), Tag (2018), The Beach Bum, Greed (both 2019), and Blithe Spirit (2020). She has also voiced characters in animated films such as Horton Hears a Who! (2008), Rango (2011), Rise of the Guardians (2012) and Back to the Outback (2021).
Outside film, Fisher played a recurring role on the fourth and fifth seasons of the sitcom Arrested Development (2013, 2018–2019), and has starred on the comedy drama series Wolf Like Me since 2022. Fisher has authored two young adult novels and the Marge in Charge book series. She is married to Sacha Baron Cohen, with whom she has three children.