Characters played by Katharine McPhee
Self
Characters played by John Rhys-Davies
General Haig
Characters played by Hugh Bonneville
Narrator
Characters played by Kelly Clarkson
Self
Characters played by Josh Groban
Self
Characters played by David Foster
Self
Characters played by Gavin Rossdale
Self
Characters played by Randy Jackson
Self
Characters played by Joss Stone
Self
Characters played by Hannah Friedman
Self
Characters played by John Debney
Self
Characters played by Robert Cait
Burt McMurtrie
Characters played by Siedah Garrett
Self
Characters played by Shelea Frazier
Self
Characters played by Anggun
Self
Characters played by Rolando Villazón
Self
Characters played by Ailee
Self
Characters played by Kevin Michael Moran
Richard Ranaghan
Characters played by Tony Eccles
Corporal Thomas
Characters played by The Vienna Boys' Choir
Themselves
Characters played by Lina Makhoul
Self
Characters played by Griffith Frank
Bing Crosby