Unlockable Characters:

• Kat - Complete arcade mode on the beginner setting with all Platinum Records. 

• Harmony - Complete arcade mode on the intermediate setting with all Platinum Records. 

• Martin - Complete arcade mode on the advanced setting with all Platinum Records. 

Unlockable Songs:

• "Ladies' Night" - Complete arcade mode on the beginner setting with at least all Gold Records. 

• "Science Genius Girl" - Complete arcade mode on the advanced setting with at least all Gold Records. 

• "Smooth Criminal" - Complete arcade mode on the intermediate setting with at least all Gold Records. 

• "One Week" - Complete Showtime mode.

Thanks to RamirezXsJ