When the Beavers win a trip to Branson, MO, they get their little sisters to come over and check on the dam. But their video taped instructions develops a severe glitch, and the little girls wind up doing all sorts of crazy things to the dam thinking it's what their brothers want.

The Beavers' annual winter bulk-up gets derailed when Dag's hyper metabolism won't let him put on weight.

In yet another scientific misadventure, Scientist #1 and Pete enlarge Dag to an enormous size so they can drive their plush custom van around inside him and learn the secrets of the pointy weasel thingys. It's up to Norb to stop them and return his brother to normal.

Everyone, especially Norb, is relieved when Dag decides to mimic his comic book hero Muscular Beaver and go into disillusioned retirement. His retirement is short-lived when he discovers that all along Norb has secretly enjoyed dressing up as his nemesis Baron Bad Beaver. The boys must fight one more super battle to end all super battles.

A mysterious present arrives for the boys on the day before their birthday, allegedly from their mother. Soon the package is driving the Beavers crazy displaying all sorts of weird behavior and eventually chasing them all around the dam.

A surprise visit from mom turns out to be even more surprising when the boys find out she's a super secret agent who's routinely called upon to save the world.

Norbert wants to complete his celebrity curling iron collection by winning the prized Bo Donaldson curling iron. To do this, Norb attempts to sell chocolate to help poor, helpless squirrels who are nutless. When Norb enlists Dag as his salesman, things get crazy when Dag tries to sell one candy bar for $200, while Norb eats himself into a chocolate frenzy.

When two Canadian beavers claim the Beavers' pond for Canada, the boys are forced into a goofy competition to reclaim what's rightfully theirs, eh.

All is vanity when Dag takes Norb's words to heart that unless you love yourself others can't love you. Dag rides his goofy vain train beyond what even narcissistic Norb could imagine.

Combining elements of various outdoor games, the boys pitch and chip their way through their Beaver-rigged indoor golf course with its Quick-sand traps, soiled greens, Yahoo-filled water hazards, and full-contact putting. The game, however, soon takes a back seat when the Beavers become obsessed with which one gets to drive the way-cool golf cart.

In a twist on the puppy followed me home story, Dag sneaks a killer whale from a marine park to the pond. The predator soon wreaks havoc on the Beavers and their forest friends.

The boys learn a lesson in hospitality and manners when they visit Big Rabbit's house and meet his rough and tumble family. Dag digs their crazy lifestyle and goes with the flow, but Norb's sense of civility is sorely tested.

A Dr. Seuss type creature appears in the dam to show the boys how to play nice, safe and fair. But he goes too far when he tries to make Dag's environment perfectly nice, safe and fair by removing his brother Norb.

Dag buys an Easy-Clone oven at a garage sale, much to Norb's amusement. He knows the toy really only makes lame plastic duplicates of things. Frustrated, Dag ignores the directions, and in no time Norb has to deal with a dam jammed with duplicate Dags.

Through the mystical powers of The Lady Of The Lanes, Laverta Lutz, Dag gets to see what Norb and their friends lives would be like if he'd never been born. He's peeved to find out they'd all be much better off, and winds up making a mess of their new lives.

In this truck drivers tale, Norbert and Daggett become embroiled in a race to the Largest Pile of Toenails Attraction with none other than Truckee and his Big Renee.

Norb checks the paper and sees a pair of the Mark 5 Model X-Ray Glasses that he must have! So instead of taking money out of his rich bank account, he goes "halves" with Dag and takes all his money! Soon Norb gets the glasses. He puts them on and all he sees is human hand bones. The real X-Ray glasses are invisible, and Dag's wearing them.

The boys go camping and Norb decides to spice up the night with a scary tale to scare his younger bro. Trouble is he ends scaring himself and not Dag, will the Hook get him?

When the dam accidentally falls on Norb's head he develops damnesia and forgets who he is. Trying to restore his memory, Dag shows him old home videos. Norb is so shocked by how badly he used to treat his brother that he resolves not to become himself again, but instead become the always nice brother named Troy.

A raging volnado' (half volcano, half tornado) capsizes the Beavers dam during a party. Everyone escapes but Dag and Truckee. Handcuffed together, the two antagonists must escape from the sinking upside down dam. Meanwhile, Norb and the rest of the gang party in the volnado shelter not missing Dag or Truckee at all.

Dag takes Norb's admonition to grow up to the extreme. Acting like his goofy version of a grownup, he drives Norb to distraction and makes him see growing up ain't all it's cracked up to be.

The boys get suckered into working in a broken down carnie by the sleazy owner, Smelly Jim. They find out it's not all fun and rigged games, but after considerable abuse get back at their tormentor in the end.

Dag purchases a white ant farm' and unwittingly releases a colony of termites who slowly devour the dam. As the boys battle the persistent insect invader, Dag's nerve fails and he joins the colony. Norb must save his brother, while also fighting off the termites alone!

Daggett and Norber are roller skating to see an ice show along with their sisters, Stacey and Chelsea. Although because of Dag, now that are stuck way at the back of the line. Norb assures the little girls they will be in soon. Meanwhile he sends Dag off to buy stuff for their sisters.

After a wizard mistakenly sends a doofy warrior to the Beaver's pond, the boys can't seem to get rid of him or his wielding sword.