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. 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. His fame in Japan landed him on the front cover of AN Magazine in Japan in March 2016 and later that year he secured a lead role in the series ZAPS, Inc., the feature Jojo's Bizarre Adventure, and a supporting role in Pacific Rim: Uprising. In 2017 he won the Best New Talent Award at Japan Academy Awards for his role in Chihayafuru.