On the Title screen -where players see "Press Start" - enter the 
following code using the Control Pad: B, A, R, R, A, C-Right, Up, 
Down, A. There will not be any indication that the code has worked. 
Select "Replay Mission" from the main menu, then press the L Button 
to display all of the missions (the R button chooses which side you 
are playing).