November, 1916. Indiana Jones and Remy Baudouin have managed to get a transfer from the European trenches to the plains of Africa. On arrival they both receive a promotion to the rank of lieutenant in the Belgian Army. When they take the wrong train they end up in Moshi. Desprerate to join their unit in Lake Victoria, the two men bump into the 25th Royal Fusiliers, a unit of cranky old men led by Indy's old acquaintance Frederick Selous. Indy's passing knowledge of trains and fluent German comes in handy for the Fusiliers, who are about to go on a mission to find and destroy a Phantom Train that carries an enormous German artillery gun. After accomplishing their goal, Selous tricks Indy and Remy into joining his unit for another caper involving the capture of the German military strategist Colonel Von Lettow-Vorbeck.

Professor Indiana Jones attends the auction of a Degas painting 'The Woman at her Toilet' which he claims to mean the world to him. He explains how he got involved in a quarrel between Degas and young Pablo Picasso in Paris, 1908. While there, Indy befriended a young American boy named Norman Rockwell and together they learned to appreciate the nuances of modern art.