Hildur Guðnadóttir's Joker

Written for the University of Hertfordshire. (2025)

Joker (2019) is a psychological thriller that explores the story of Arthur Fleck, a party clown and failed stand-up comedian, who leads an impoverished life with his mother in the chaotic Gotham City (IMDb, 2019). Directed by Todd Phillips, the film portrays how Arthur’s alienation and social rejection culminate in the Bathroom Scene, a pivotal moment where, after he commits murder, his metamorphosis into the Joker, DC’s all-time supervillain, begins (IMDb, 2019). This paper examines how Hildur Guðnadóttir’s score narrates Arthur’s transformation by pre-establishing a sonic world and crafting an ambiguous diegesis that merges score and performance into a single psychological event.

Before Bathroom Dance, Guðnadóttir foreshadows Arthur’s transformation by establishing the Joker’s sonic identity before it unfolds on screen. Contrary to the conventional scoring timeline, Guðnadóttir was approached early in the process by Phillips, allowing her to discover the story’s sonic identity directly from the script in an organic, pre-visual process (Kron, 2020). Guðnadóttir refers to Joker’s score as a character study, where thematic intention and profound character awareness lead over underscore (Goldowitz, 2019). By translating her emotions and physical reactions the script provoked in her into sound, Guðnadóttir built a sonic world for Arthur that stemmed from intention rather than superficial reaction (Tangcay, 2019). As Guðnadóttir said herself, "I'm just holding onto this feeling that I had after reading the script. As soon as I played those first notes, it really hit me in the chest” (Greiving, 2019). This sonic world was built around the idea of using a cello to represent Arthur’s voice, which was gradually overwhelmed by an orchestra as his descent into madness unfolded (Greiving, 2019). Hence, before the audience experienced Arthur’s mental collapse and first steps into madness, Guðnadóttir had presented an intentionally profoundly crafted sonic world, positioning Bathroom Dance as the sonic revelation of Arthur’s true identity within an established musical framework (Moreau, 2019).

In Bathroom Dance, Guðnadóttir narrates Arthur’s transformation by blurring Arthur’s inner and outer worlds, drawing on her creative process and artistic collaboration. Firstly, she achieved this by selecting a halldorophone instead of a cello, which imbued the scene with an eerie instability (Roberts, 2019). Unlike a cello, the halldorophone works through a microphone that detects string vibration, amplifying and routing it back to the speaker at the back of the instrument. Given its timbral instability, harmonic stasis and feedback sensitivity, as gain can be controlled individually per string (Robson, 2020), its chaotic nature allowed Guðnadóttir to exacerbate Arthur’s fragile and volatile psyche. Consequently, the halldorophone's eeriness and expressive control became a voice to parallel Arthur’s psychological trajectory as he navigated his newly found, maddening empowerment after committing murder. Secondly, Guðnadóttir crafted the Joker’s theme, Bathroom Dance’s main idea, before shooting began, and Phillips defied conventional scoring again by allowing Joaquin Phoenix, the lead actor, to improvise the scene’s choreography to the music, crafting a moment of true artistic collaboration (Kron, 2020). This created a moment in which score and performance fused, generating an intense sense of diegetic ambiguity (Shine, 2024). Gotham City cannot hear Guðnadóttir’s music, and yet Arthur dances to it, illustrating the fight between Arthur’s fragile touch on reality and the Joker’s malicious need to surface. As a result, as the cue progresses, the gradual shift from fragility to resonance mirrors Arthur’s movement from victimhood to self-possession, like cinematographer Lawrence Shed described, "The score was such an instrumental part, not just to Joaquin's performance, but to the camera operating, to the sort of energy in the room, and to make that scene really come alive" (Greiving, 2019).

Guðnadóttir's score narrates Arthur’s transformation into the Joker through pre-compositional groundwork, a carefully chosen instrumental voice, and a collaborative process that blurs the line between diegetic and non-diegetic sound. These choices from Guðnadóttir enabled Phillips and Phoenix to use synchresis to externalise Arthur’s internal transformation through embodied performance, as the music transcended underscore and illustrated Arthur’s psychological rebirth as the Joker. For further research, the next step would be to identify other directors and composers who have employed a similar approach and those who have not, and compare the impact on the audience.

From Joker (2019)

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Guðnadóttir, H. (2019). Bathroom Dance. WaterTower. Available at: https://www.youtube.com/watch?v=8z5-Wum2enQ [Accessed 6 Oct. 2025].

IMDb (2019). Joker. [online] IMDb. Available at: https://www.imdb.com/title/tt7286456/ [Accessed 6 Oct. 2025].

Joker. (2019). [Theatrical Release] California, United States of America: Warner Bros. Pictures. Bathroom Scene: https://www.youtube.com/watch?v=BBY4zUFxUjA.

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Robson, N. (2020). The Halldorophone. [online] nicolerobson.com. Available at: https://nicolerobson.com/dual-duel-duet.html [Accessed 6 Oct. 2025].

Salisbury, M. (2020). How ‘Joker’ Composer Hildur Gudnadottir’s Music Was Used to Inspire the Actors on Set. [online] Screen Daily. Available at: https://www.screendaily.com/features/how-joker-composer-hildur-gudnadottirs-music-was-used-to-inspire-the-actors-on-set/5146783.article [Accessed 6 Oct. 2025].

Shine, J. (2024). ‘He Has Music in Him’: Musical Moments, Dance and Corporeality in Joker (2019). Alphaville, [online] 27(27), pp.152–168. doi:https://doi.org/10.33178/alpha.27.14.

Tangcay, J. (2025). Interview: Hildur Guðnadóttir Discusses Composing the Score for ‘Joker’. [online] Awards Daily. Available at: https://www.awardsdaily.com/2019/10/04/interview-hildur-gudnadottir-discusses-composing-the-score-for-joker/ [Accessed 6 Oct. 2025].