Mackenyu was born in Los Angeles and and began acting in his teens. His career took off in Japan in 2015 when he starred in three supporting roles in TV Mini-series and as one of the leads in the live action movie Kamen Rider Drive: Surprise Future. In January 2016 he made his stage debut in the Japanese musical Boys Over Flower and was a lead in the two part feature film Chihayafuru Part I & II. In 2016 he also secured supporting roles in the feature films Jojo’s Bizarre Adventure: Diamond Is Unbreakable (2017), and Pacific Rim: Uprising (2018), and a lead role in the series ZAPS, Inc. (2018). In March 2017 he won the Best New Talent Award at Japan Academy Prize for his role in Chihayafuru and was nominated for his role in the film for both the 41st Hochi Film Award and the 71st Mainichi Film Awards.