- Newly created Oedekerk character The Thumb from Thumb Wars is seen briefly licking a giant ice cream cone.
- Woody Woodpecker made a cameo when Agent Tommy Clark hit the players.
- Jimmy Neutron made a cameo appearance when Agent Jackson Robinson hit Mary's head.
- Bart Simpson made a cameo when Agent Mickey Moore hit the ground.
- When Agent Lois watched a Max Fleischer's Cartoon Capers VHS, Kang and Kodos appear in a dream sequence.
- Bugs Bunny made a cameo when Agent Rob watched The Wizard of Oz VHS.
- When Agent James watching a fictional show Wombats!, Elmer Fudd, Tweety and Sylvester made a cameo appearance.
- Betty Boop and Little Audrey made a cameo when Agent Shirley Beck hit the trash can.
- As the credits scrolled, the agents' completed film Mystery Manners is shown. Little Lulu and Casper walks over.