Rocky, Bullwinkle, Casper and the gang took a trip to the old western town to visit Dudley cousin.
In the old western town, Dudley and his cousin, Abraham were trapped by the villains. But they don’t know how did everything happened so the narrator rewind the story to the beginning that it’s all started when Dudley shows all of his friends and family, Rocky, Bullwinkle, Casper, the Ghostly Trios (Stretch, Stinkie and Fatso), Mr. Peabody, Sherman, Wendy, the Witch Sisters (Gerti, Gabby and Fanny), Spooky, Nell and Poil that he got a letter from his cousin, Abraham and it’s said “Dear Cousin Dudley, I need your help because I've been trapped by those villians. Please! Save me! Signed, Abraham." Rocky, Bullwinkle, Casper and the gang are all shocked because Dudley cousin is in trouble and that couldn’t been Boris, Natasha and Snidely who are doing this so they must go to Western Town immediately.
Meanwhile at the old western town, two Indian princesses, a gray puma cat, Princess Kiona of the Indian Cats and a bright pink ghost, Princess White Snow of the Ghosts Indian are on the treasure hunt looking for a birthday present for Sheriff Boo-West of the Haunted Western Town, who lives in the rabbit hole. As Kiona and White Snow found some two treasures they saw a ghost bear and it scared them away. After the chase, Kiona and White escape so they can bring the birthday present to the ghost sheriff. Later in the rabbit hole, Boo-West is still waiting for Abraham and wonder why he hasn’t showed up yet, but something's missing. At least, Kiona and White Snow made it with their presents to Boo-West and gave them some two treasures, and need their help.
Kiona, White Snow and Boo-West went to see a scientist cowgirl, Sandy-Rosie Clayton and her cowboy wizard friend, Puck and ask them why Abraham haven’t come to Boo-West birthday, Puck summits a magic minor and it’s telling them that Abraham is Dudley's long lost cousin in the west but he is being kidnapped by those villains. Later Rocky, Bullwinkle, Casper and the gang arrives and looking for Dudley cousin in the rabbit hole. Then the gang finally meet Kiona, White Snow, Sandy-Rosie, Puck and Boo-West who told them that they know Abraham is been kidnapped by those villains and now they are teaming up with the western gang so Dudley, Spooky, Nell and Poil team up with Boo-West to go north way, Mr. Peabody, Sherman, Wendy and the Witch Sisters team up with Sandy-Rosie and Puck to go south way and Rocky, Bullwinkle, Casper and the Ghostly Trios team up with Kiona and White Snow to go east way. Casper is going to inflate his belly like a hot air balloon and go find Abraham with Rocky.
As Casper and Rocky are search for Abraham, they found a familiar place like zombie goth where they see Boris, Natasha and Snidely who meet a human prospector, Cowboy Harry Sanderson who has Abraham all tie up so Casper and Rocky must get rid of those zombies. As they got rid of the zombies, Boris, Natasha, Snidely and Cowboy Harry saw them so Rocky and Casper escapes so quickly and hurry back to Bullwinkle, Kiona, White Snow and the Ghostly Trios to warn that it's Boris, Natasha and Snidely who got Abraham so Casper's got an idea.
Rocky, Bullwinkle, Casper, Kiona, White Snow and the Ghostly Trios hurry up to the south way to warn Mr. Peabody, Sherman, Wendy, Sandy-Rosie and Puck about it and they cannot believe it and they all went to the north way to warn Dudley, Spooky, Nell, Poil and Boo-West about it too and they can't believe it neither so they must go back to zombie goth immediately. Bullwinkle inflates Casper's belly again with the air tank and want him to find Abraham again with Rocky. As Casper and Rocky lead the gang to the zombie goth, Dudley and Boo-West can't believe Boris, Natasha and Snidely team up with Prospector Cowboy Harry to tie up Abraham so Dudley and Boo-West want Casper and Rocky to stop those bad guys.
As Rocky and Casper try to stop those villains, they have been captured by them, Bullwinkle, Kiona, White Snow and the gang try to rescue Rocky, Casper and Abraham, they've got caught too. As Boris, Natasha and Snidely put Bullwinkle, Kiona, White Snow and the gang in the cage with Abraham, Cowboy Harry close the door on Boris, Natasha and Snidely and have them trap with the heroes. Boris, Natasha and Snidely realize that Cowboy Harry double crossed them and having a tantrum. Cowboy Harry told them that it's just business so he turn out to be a hairy ghost clown in disguise as the Ghostly Trios realize that it's their long lost cousin, Hairy Scary who try to use his revenge on Casper the last time they see him because those costumes are fake.
After Hairy Scary left with Rocky and Casper, Dudley is glad that Abraham is okay and he and Boo-West were so worried about him and Abraham apologized for missing Boo-West's birthday party and the big adventure. But Bullwinkle told the gang that he is so worried about Rocky because they are always best buddies and the Ghostly Trios are very worried about Casper because Hairy Scary is the worst. Because Hairy Scary use to be a good guy to help Casper by teaming up with the angels officers, helping the orphans to save Halloween and help Yogi Bear and his pals to celebrate Christmas. Bullwinkle has an idea to save his best buddy and the trios nephew so he send a message to Jellystone Park just like Abraham send a message to Frostibite Falls last time to get Yogi Bear and his gang to come rescue them.
Meanwhile at Jellystone Park, Yogi Bear has a big plan. He told Booboo, Penelope Pitstop, Huckleberry Hound, Quick Draw McGraw, Snagglepuss, Augie and Doggie Daddy, Big Gruesome, Little Gruesome, Peter Perfect, and Yakky Doodle to get rid those bad guys and monsters. So Yogi and his friends hurry up to the haunted western town to free Bullwinkle, Kiona, White Snow and the gang including Boris, Natasha and Snidely because they feel sorry for teaming up with the fake prospector so they decided to join the gang to rescue Rocky and Casper from Hairy Scary. Until, this is a disaster. Dick Dastardly and Muttley came to help the gang to save the day.
At the lava monster lagoon, Hairy put Casper and Rocky in the tickling monster factory. Then suddenly, Bullwinkle and Yogi Bear are going to save Rocky and Casper. Boris, Natasha and Snidely reminds Dastardly and Muttley that Hairy disguise as the human prospector to use them to kidnap Dudley's cousin and then double crossed them after trap the heroes and Dastardly and Muttley are not very happy about that so they demanded Hairy to seize them. But Hairy refuses so Bullwinkle and the Ghostly Trios begin to fight Hairy as Kiona and White Snow jump to release Rocky and Casper and then Casper is going to make a big deep breath to make his belly swollen and then he blow the bad guys away.
Hairy is very angry as he try to harm Casper for doing that, White Snow use her ghostly power to stop Hairy and put him in the tickling monster machine. After that Boo-West arrests Hairy for kidnapping his best human friend, double cross Boris, Natasha and Snidely and revenge on Rocky and Casper and Boris reminded Hairy "Nobody try to revenge on a squirrel but he and Natasha". Kiona and White Snow returns Rocky and Casper to Bullwinkle and the Ghostly Trios who save the day!" The gang are cheering very happily with the THE END logo.
- The Ghostly Trios (Stretch, Stinkie and Fatso)
- Mr. Peabody
- The Witch Sisters (Gerti, Gabby and Fanny)
- Dudley Do-Right
- Nell Fenwick
- Snidely Whiplash
- Abraham Do-Right
- Sheriff Boo-West of the Haunted Western Town
- Princess Kiona of the Indian Cats
- Princess White Snow of the Ghosts Indian
- Sandy-Rosie Clayton
- Puck the Cowboy Wizard
- Hairy Scary/Cowboy Harry Sanderson
- Yogi Bear
- Boo Boo
- Penelope Pitstop
- Huckleberry Hound
- Quick Draw McGraw
- Augie Doggy & Doggie Daddy
- Big Gruesome & Little Gruesome
- Peter Perfect
- Yakky Doodle
- Dick Dastardly & Muttley
- Jodie Resther as Rocky, Casper, Natasha, Sherman, Gerti, Gabby, Fanny, Nell Fenwick, Princess Kiona, Princess White Snow, Sandy-Rosie Clayton, Little Gruesome, & Penelope Pitstop
- Bill Farmer as Bullwinkle, Boris, Stinkie, Dudley Do-Right, Snidely Whiplash, Abraham Do-Right, Sheriff Boo-West, Puck the Cowboy Wizard, Hairy Scary, Yogi Bear, Boo Boo, Huckleberry Hound, Snagglepuss, Quick Draw McGraw, Augie Doggie, Doggie Daddy, Big Gruesome, Peter Perfect, & Dick Dastardly
- Melissa Altro as Wendy & Poil
- Jason Marsden as Spooky
- Arthur Holden as Mr. Peabody
- Tom Kenny as Stretch
- Bill Fagerbakke as Fatso
- Tony Anselmo as Yakky Doodle
- Scott Innes as Muttley