He is also known for having played Charles Manson twice, first on the second season of the Netflix psychological crime thriller series Mindhunter, and later in the comedy drama film Once Upon a Time in Hollywood (both 2019).

He continued to work solidly as a child actor, with a return to The Sullivans a year later, as well as the Australian series The Patchwork Hero, Sara Dane, For the Term of His Natural Life and Taurus Rising.

[1] After appearing in The Flying Doctors, for which he won the Penguin Award for Excellence in a Performance by a Juvenile, and the children's mini-series Elly & Jools, Herriman was cast as Mark Jorgensen, the bespectacled best friend of Ben Mendelsohn's Danny Clark in the Australian cult comedy classic The Big Steal.

He played the convicted kidnapper of the Lindbergh baby, Bruno Hauptmann, in the Clint Eastwood-directed J. Edgar (2011),[4] and one of the Cavendish gang in Gore Verbinski's The Lone Ranger (2013).

[7] In 2019, he appeared as Paul Allen Brown in Steven Conrad's Epix series Perpetual Grace, LTD.[8] In 2021, he was the voice of Kabal in Mortal Kombat, with stuntman Daniel Nelson portraying the character in the suit.