MardukCorp is in meltdown. Part of their manufacturing process met an explosive end, and they're scrambling to put the pieces back together… at least, they should be? Instead, everything seems normal at the office – except the MarduKard testing interns are called in for overtime, and a little investigating shows their numbers are falling fast. The company must have something else up its sleeve, and Riko and the gang are determined to find out what it is. Fortunately, they meet some new friends who know their way around town – and the secret passages around the MardukCorp underground. Will the bonds of their friendship survive the dark secrets they unearth…?