In his earlier days, Halliday seems to have relished the life of an adventurer. At one time he fought with the British Army during the Boer War. As a mining engineer he then dug for gold nuggets in Nevada, rapidly made a fortune and lost it as quickly. He eventually switched to the more peaceful pursuit of acting, initially in Gilbert & Sullivan operettas, then in dramatic plays on Broadway from 1912 to 1936 (lastly in "Tovarich", as Prince Alexandrovitch). Though Brooklyn-born, Halliday was raised in England and often adopted an upper-crust British accent. An incisive and debonair actor with a penchant for sophisticated comedy, he received good reviews as co-star of The Woman Accused (1933) with Cary Grant and Nancy Carroll. He was very much at home playing caddish bon vivants, gleeful villains (such as in Terror Aboard (1933)) or wily arch rogues (notably Desire (1936) with Marlene Dietrich). Halliday had another pivotal role in Intermezzo (1939) and was then cast to best advantage as Katharine Hepburn's charming philanderer of a father in The Philadelphia Story (1940). He died in Honolulu, Hawaii, from a heart ailment in October 1947 at the age of 67.