When Daggett gets captured during a fight with Toe-Bot as Muscular Beaver, Norbert reluctantly becomes a superhero in order to rescue his brother, despite the fact that he wished to hold a party. Fortunately for Norbert, many of his friends are willing to accompany him and they become The Justice Guys (and One Gal), in an attempt to take town Toe-Bot.
- Fifth time Dag dressed up as Muscular Beaver. ("Gift Hoarse", "Muscular Beaver", "Muscular Beaver 2", "Muscular Beaver 3")
- Fourth time Norb dressed up as Baron Bad Beaver. ("Muscular Beaver", "Muscular Beaver 2", "Muscular Beaver 3") Although, the name is now "Baron Once-Bad-Then-Good-Then-Bad-Again-Now-Good-Again Beaver".
- Treeflower gives herself the superhero name "Goody Good Gal", the same name that Muscular Beaver (Daggett) gave her when he appointed her as his sidekick. ("Muscular Beaver 3")
- The Beetle - The comic-book panel picture of Bing's super-heroic identity resembles the Marvel Comics super-villain.
- Fantastic Four - The number in the episode title is drawn the same as the logo worn by the Fantastic Four.
- Wonder Woman - With the exception of the cape, Treeflower's Goody Good Gal costume resembles the one worn by the DC Comics super-heroine.
- Ritz Crackers - Blitz Crackers is a spoof of the Nabisco snack cracker.
- "Let's Stay Together" - Barry sings a song similar to Al Green's 70's hit in order to save Daggett from Toe-Bot.
|The image gallery for Muscular Beaver 4 may be viewed here.|
- Nick Bakay as Norbert
- Richard Horvitz as Daggett
- John Garry as Barry
- Cynthia Mann as Treeflower
- Victor Wilson as Bing
- Mark Klastorin as Truckee
- Mitch Schauer as Narrator
"Stump's Family Reunion"
"Act Your Age"