J. J. Sawyer
Successfully complete the game with an "S" rank in all levels.

Naomi
Successfully complete the Downtown level with a "B" rank.

Oscar
Successfully complete the game with an "A" rank in all levels.

The Insider
Successfully complete the Storage level with a "B" rank.

Stunt Attack Mode
Successfully complete the game in story mode.

Alternate Costumes
Complete one of the following tasks to unlock a third costume for the indicated character.

Ethan: Successfully complete stunt attack mode.
Kat: Successfully complete score attack mode with high scores in all levels.