He has appeared in leading roles in the feature films Adore, September,[1] Further We Search,[2] Newcastle,[3] The Loved Ones,[4] Frankenstein, A Few Best Men, and played Riley Biers in The Twilight Saga: Eclipse, and Billy in Spin Out.

[11] Alongside Mia Wasikowska, Samuel was in 2007 the Australian film September, set in 1968 where two young boys who share a passion for boxing are friends.

[15][16] In 2013 he played Ian in Adore beside Robin Wright and Naomi Watts, which is based on Doris Lessing's book and directed by Anne Fontaine.

[7] Anne Fontaine coached Samuel through rehearsals of the love scenes in a hotel room using a paid actress who stood in for Wright.

[7] In 2014, Samuel was cast alongside Brad Pitt and Shia LaBeouf in the $80 million blockbuster Fury, about a group of Americans in Nazi Germany at the end of World War II.

[7] In 2016, Samuel played the titular character in The Death and Life of Otto Bloom, with Rachel Ward and her daughter, Matilda Brown.

[19] In the same year, Samuel performed alongside Kate Beckinsale, Chloe Sevigny, Stephen Fry, and James Fleet in the critically-acclaimed film Love and Friendship, adapted from Jane Austen novel Lady Susan.

[8] Starring alongside Hugo Weaving yet again, Samuel played the role of Simon Heywood in the Australian TV series, Seven Types of Ambiguity in 2017.

[21] In 2022, he starred in the Marilyn Monroe bio-pic Blonde, written and directed by Andrew Dominik and adapted from the 2000 novel of the same name by Joyce Carol Oates.