The main four and the bunny twins go on vacation, but a plane crash results in the main four getting stranded on an island with Kaeloo and Stumpy on one side and Mr. Cat and Quack Quack on the other. The bunny twins, who landed back home, try to rescue them.
"Let's Play Castaways" contains the following tropes:
- Ascended to Carnivorism: Stumpy attempts to eat Kaeloo and Eugly.
- Chain of People: When it looks like Quack Quack is about to fall off the plane, Mr. Cat grabs his hand to save him. The bunny twins also get flung off and Eugly grabs Quack Quack's foot and Pretty grabs Eugly, creating a chain of people. Since Mr. Cat hates the bunny twins, he chops Quack Quack's legs off with a chainsaw and Pretty and Eugly are flung off the plane.
- Dude, She's Like in a Coma: Enforced. Pretty knocks Mr. Cat out cold so that she can kiss him.
- Kiss of Life: Pretty finds Mr. Cat, who has been stranded on an island, and offers to do this. He declines and points out that he's perfectly fine, so she knocks him out with a baseball bat and gives it to him anyway.
- No Party Like a Donner Party: Stumpy tries to eat Kaeloo while they are stranded on the island. He can later be seen gnawing on Eugly's ear.
- Social Media Before Reason: Pretty decides to post pictures of herself crying over the main four being stranded on an island, rather than, as her sister points out, rescuing them.
- Something We Forgot: After they reach home, Kaeloo, Stumpy, Quack Quack and Eugly realize that Mr. Cat and Pretty are still stranded on the island. The scene cuts to Pretty chasing Mr. Cat around while the latter screams for help.
- Time-Passage Beard: Parodied. Stumpy, who is a kid, somehow grows a gray beard after being stranded on an island for less than a day. So does Kaeloo, who is also a kid... and female.
