
Thomasin Harcourt McKenzie (born 26 July 2000) is an actress from New Zealand. After a minor role in The Hobbit: The Battle of Five Armies, she rose to critical prominece with the lead role in Debra Granik's 2018 drama film Leave No Trace. After supporting roles in the 2019 films The King, Jojo Rabbit and True History of the Kelly Gang, as well as the 2021 thriller Old, Edgar Wright's psychological horror film Last Night in Soho established her as one of the industry's lead actresses.

The Hobbit: The Battle of the Five Armies
2014 · as Astrid

Old
2021 · as Maddox Aged 16

Jojo Rabbit
2019 · as Elsa

Last Night in Soho
2021 · as Eloise Turner

The King
2019 · as Philippa, Queen of Denmark

Fackham Hall
2025 · as Rose

The Testament of Ann Lee
2025 · as Mary Partington / Narrator

The Power of the Dog
2021 · as Lola

Victorian Psycho
2026 · as Miss Lamb

Leave No Trace
2018 · as Tom

Eileen
2023 · as Eileen Dunlop

Lost Girls
2020 · as Sherre Gilbert

True History of the Kelly Gang
2019 · as Mary Hearn

Joy
2024 · as Jean Purdy

Rule of Three
as Lizzy

The Uprising
2026

The Changeover
2017 · as Rose Keaton

Grendel
as Queen Wealhtheow