John's most famous television role is undoubtedly that of sci-fi hero Captain Jack Harkness, whose first appearance in the revamped Doctor Who created such an impact that he was given his own spin off series, Torchwood. He was a recurring star on Titans, Central Park West, and Desperate Housewives, and now can be seen as the villainous Malcom Merlyn across the CW's Arrow, The Flash, and Legends of Tomorrow. In film, John starred in Kathryn Bigelow's Oscar-winning Zero Dark Thirty alongside Jessica Chastain, Mel Brooks' The Producers, and Irwin Winkler's 2004 ode to Cole Porter, De-Lovely.
A staple in British musical theatre, John’s career as a leading man 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.
John's extensive list of professional achievements is only surpassed by the unwavering love and dedication he and husband Scott Gill have shared over their twenty-five year long relationship.