Nermal adds himself into his film. Miss Kitty exposes Dr. Whipple's plan to Garfield, Odie and Jon. They are accompanied by Rupert and Nermal to Glitter Gulch. But Garfield, Dr. Whipple and the others discover what's guarding the gold.
Squeak is telling the Mole that Nermal is busy talking to the head of the studio. Nermal makes the head of the studio guess on who is in the film. He guesses all three wrong and Nermal tells him that he is adding himself to the the film which makes the head of the studio laugh. Nermal and the film crew resume filming.
Dr. Whipple and his henchmen leave to go and find Glitter Gulch in wagons to bring back a lot of gold which the map will tell them where it is. Meanwhile at a hotel, Jon tells Garfield and Odie that he is going to look for a job. Garfield and Odie become suspicious about Dr. Whipple. Miss Kitty visits them and Garfield reveals that he found out that she was working for Dr. Whipple. Miss Kitty tells them and Jon about Dr. Whipple's plan and that The Mustache Mob are Clyde, Zeke and Luke without their mustaches. Garfield, Jon and Odie wonder how they will get to Glitter Gulch. Rupert comes to them and reveals that he was the one who found Glitter Gulch 57 years ago. He agrees to lead them to Glitter Gulch but won't go into the canyon because of the lizards that scared him off. Garfield and Odie see Nermal next to him. Garfield tells Nermal that he was supposed to be directing and Nermal tells him that the film needed something and that he wanted to be a star. Nermal tells the gang that they won't need horses and brings limousine in. Garfield tells Nermal that there were no limousines in western films. Nermal reminds him that there were no Zombies, Ninjas or talking cats either to which Garfield agrees.
Meanwhile Dr. Whipple tells Luke to go where the map tells them while Rupert tells the driver of the limousine where to go. Rupert tells them again that he will be waiting outside the canyon with the car. Jon thinks that a group of lizards isn't going to keep Dr. Whipple away from the gold. Dr. Whipple and his henchmen arrive and enter the canyon which they find a lot of gold making the legend of Glitter Gulch real. Garfield and the others also arrive and tell them that they are going to hand them in to jail. Clyde, Zeke and Luke remind them that they are the sheriff and deputies. Jon and the others don't care because they are still going to tell everyone of the plot. Dr. Whipple tells his henchmen to shoot them with pies. But everything is interrupted by 5 Tyrannosaurus Rex in which Rupert meant by lizards. Nermal is pleased that the movie needed dinosaurs. The T-Rexes are revealed to be the ones guarding the gold and chase everyone. Garfield asks Nermal on why he never knew that there was going to be dinosaurs in the movie and that he thought Nermal wrote the script. Nermal tells him that he left it to a guy who writes science fiction movies. Clyde, Zeke and Luke tell Dr. Whipple to leave the gold but Dr. Whipple refuses to leave it. Jon and the others make it out. Dr. Whipple can't get out with the gold in the bags. Garfield tells him that he will have to drop the nuggets and leave the gold in which Dr. Whipple finally does. Jon saves him from being eaten.
Everyone is out and Rupert tells them that is why he doesn't like lizards. The Mustache Mob after what happened to them in the canyon decide to surrender making Jon, Garfield and Odie the sheriff and deputies again. The T-Rexes still guard the gold. Dr. Whipple and his henchmen are put into jail after they get back to the town. Arlene and Miss Kitty have now become friends, they both admire Garfield and agree that Arlene and Garfield will make a wonderful couple.
On the set Nermal is talking to the head of the studio who thinks the film needs a better ending.
Arlene and Garfield are walking together. Garfield promises to eat healthy food. He reminds the audience that this is a film and that he doesn't do it in real life. Nermal tells everyone that the film needs a better ending. He lets the Zombie, Ninjas, Eddie Gourmand, Vito Cappelletti in. He also lets the dinosaurs in which leads into a chase and happy ending song. The Zombie for the end tries to do a trick with the pies and fails.
- Dr. Whipple
- Miss Kitty
- Rat with guitar
- Eddie Gourmand
- Vito Cappelletti
- Herman Post (cameo)
- Pet Show Host (cameo)
- Mr. Albert (cameo)
- Ralph (cameo)
- Mr. Connors (cameo)
- Bruno (cameo)
- Angie (cameo in poster)