Born on 11 March 1967 in Glasgow, where he spent his early years, John moved with his family to Illinois in the United States and later studied Musical Theatre at the US International University in San Diego, California.
In 1989, while in the UK to study Shakespeare as part of his university course, he landed his first professional role starring as Billy Crocker opposite Elaine Paige in the Cole Porter musical Anything Goes.
Since then, John’s career as a leading man in musical theatre has seen him star in many West End shows, including Matador, Miss Saigon, The Phantom Of The Opera and Sunset Boulevard. He also reprised the role of Joe Gillis in Sunset Boulevard on Broadway. Sam Mendes' premiere production of The Fix at the Donmar Warehouse garnered John an Olivier Award nomination as "Best Actor in a Musical", and in 2002 he returned to the role of Billy Crocker for the hugely successful National Theatre revival of Anything Goes.