Sienna Shaw is a fictional character in the Terrifier franchise. Sienna first appears in Terrifier 2 (2022) as a teenager interested in cosplay who battles the enigmatic villain Art the Clown. She is portrayed by Lauren LaVera, who will reprise the role in further installments. Sienna's creator, Damien Leone, invested a lot of time into fully developing her as a character as he regretted leaving the first film's heroine Victoria Heyes underdeveloped. The character originates from an abandoned film Leone was developing in the late 2000s, featuring the concept of a Valkyrie-angel warrior attired heroine battling Art.

Terrifier 2 is a 2022 American slasher film written, directed, edited and produced by Damien Leone. A sequel to Terrifier (2016), it is the second film centered solely around Art the Clown and third feature-length film to feature the character. It is the fourth installment and sixth overall installment in the Terrifier franchise. It includes the return of David Howard Thornton and Samantha Scaffidi, who portrayed Art the Clown and Victoria Heyes, respectively, in the first film, and stars Lauren LaVera, Elliott Fullam, Sarah Voigt, Kailey Hyman and Casey Hartnett. The plot follows Art's resurrection and pursuit of teenage Sienna Shaw (LaVera) and her younger brother Jonathan (Fullam) on Halloween night—a year after the events of the first film.