[1] She lived with her parents, social workers Greg and Lorraine, and sister Sally in Colonel Light Gardens, and attended the local primary school.

At the age of 13 she started classes at Unley Youth Theatre (now Urban Myth), where she met filmmakers Sophie Hyde and Matthew Cormack, who went on to form Closer Productions, and screenwriter Drew Proffitt.

[2] Her performance in the 2014 comedy film The Little Death earned her a nomination for best actress in a leading role in the AACTA Awards.

[7] During her run on Rake, Box was cast in popular television series including Offspring,[8] Old School, and the six-part Closer Productions comedy drama mini-series Fucking Adelaide (2018).

[2] Box played Marg McMann in the 2018 television film Riot, a film focusing on the LGBTI rights movement and the origins of the Sydney Gay and Lesbian Mardi Gras in the 1970s,[10][2] a role which won her the AACTA Award for Best Lead Actress in a Television Drama,[11] and the role of which she is most proud, saying "I was so grateful to walk with that character for a bit because the courage that she displayed definitely helped me to live my life with more truth and courage".

Winning the AACTA for the performance was especially meaningful for her, because it gave her the opportunity to stand "front and centre" of issues relating to gay rights and acceptance of LGBTQIA+ people.

[2] In 2019, it was announced Box was cast in the role of "legacy" character Lou Kelly in the Foxtel prison drama series Wentworth for its eighth and final season.

[18][19] Box plays Dr Brennan[20] in the seven-part Netflix adaptation of Trent Dalton's novel Boy Swallows Universe, aired in January 2024.