Quack Quack wants answers to questions he has about his past. The main four use the "Big Book of Destiny" to travel to different points in their lives.
"Let's Play Big Book of Destiny" contains the following tropes:
- Character Check: After spending the majority of the past two seasons being a wonderful, loving, caring friend to Kaeloo, Mr. Cat abandons her and the others after winning the lottery.
- O.O.C. Is Serious Business:
- At the beginning of the episode, Quack Quack angrily tells off the rest of the main four for goofing around instead of helping him get to the Big Book of Destiny, which shows how much he wants to know who wrote the postcard.
- How badly is Quack Quack hurt by Mr. Cat's abandonment? He throws his yogurt eating spoon on the ground in a fit of anger with an expression of pure bitterness on his face, which is pretty shocking for an easygoing guy who usually doesn't even make facial expressions.
- Out-of-Character Moment: After becoming rich, Mr. Cat abandons the main four without even saying goodbye to anyone except Kaeloo, who gets a half-hearted "apology" which essentially consists of telling her to her face that money is more important to him than she is. It's even lampshaded by Kaeloo, who didn't think Mr. Cat would ever abandon the main four.
- Self-Fulfilling Prophecy: Stumpy finds out that the aftermath of the panini world war turned him morbidly obese because he kept eating paninis. This freaks his present self out so much that he starts stress eating paninis, which are extremely fattening.
- Status Quo Is God: Kaeloo goes back in time and prevents the events of the episode from ever happening.
- Wham Episode: Quack Quack has biological siblings, who might even live somewhere in Smileyland.
- World War III: The "panini world war" happens sometime in the next 20 years.
