[3] At Marymount, Weatherall played the role of Lonny Barnett / Record executive in the college's 2017 production of Rock of Ages.
However, he heard about ABC Television auditioning for roles in Deadlock (2018) during his last year of high school, and decided to give it a try.
[9][10] Weatherall's playwriting debut came with the play Blue, which he started writing in 2019 based on old high school diary entries, as "self-prescribed therapy".
After winning a Balnaves Fellowship to complete the play, he fictionalised it further,[6] and performed in the Belvoir Theatre production of it in Sydney in 2023.
[13][6] Weatherall is set to star opposite Jacob Elordi in the upcoming adaptation of Richard Flanagan's novel The Narrow Road to the Deep North as a TV series for Prime Video.