 Complete the following phrase:  Khartoum is a 1966 British epic war film written by Robert Ardrey and directed by Basil Dearden. It stars Charlton Heston as British Gen. Charles Chinese Gordon and Laurence Olivier as Muhammad Ahmed a Sudanese leader whose devotees proclaimed him the Mahdi, with a supporting cast that includes Richard Johnson and Ralph Richardson. The film is based on historical accounts of Gordons defence of the Sudanese city of Khartoum from the forces of the Mahdist army, during the 18841885 