Beat the game with Plo Koon. At the character screen, highlight Plo Koon and press Select. Picture should over lap Koon.
Finish the game with Qui-Gon Jinn. At the character menu screen, highlight Qui-Gon and press Select. Darth Maul should cover Qui-Gon's face.
Beat the game with Obi-Wan. At the character screen, highlight Obi-Wan and press Select. The same effect will happen as above.