When everyone ignores Scooby, he no longer feels needed, which leads him to go off on his own. Soon the kids realize, and want him back. But is it too late, when someone else wants Scooby and his head?
The gang is at the clubhouse on a rainy day; Scooby's looking to play, but ends up scolded by them one by one which deeply hurts him. He accidentally gets mud on Daphne's clothes, then rips through Freddie's subscription of the National Exaggerator, while Velma's busy with an experiment and finally licks the last of Shaggy's pizza mix. He then decides to run away on his own. Unknown to him, a mad scientist-like woman spies on him, and decides that his head would be perfect for her project, and vows to get it.
Later, the gang felt bad at how they were hard on Scooby, and go's to his doghouse to cheer him up. However, they discover that Scooby has already ran away, which horrifies Shaggy. They tell Shaggy's dad, who will call the station to help find Scooby. Shaggy doesn't want to wait for Scooby to come back, so he and the gang decide to go out and look for him—Sugie wants to help them look for Scooby, but Daphne advises her to stay home with Mr. and Mrs. Rogers, in the case that Scooby comes back before they do. As they out searching for Scooby, the gang talks about how Scooby was special to them all, and Shaggy remembers how, when he and the rest gang were very little, and Scooby caught a monster that turned out to be Red Herring, which Freddie never forgot (and is apparently the reason he typically accuses Red Herring of being the culprit in the mysteries they solve).
Meanwhile, Scooby went to the Butcher shop to get some bones from Mr. Porterhouse. Upon leaving, he bumps into Red who meanly teases him. After he leaves, he bumps into the woman who explains that he needs his head, but wouldn't say why. Scooby refuses to cooperate, so he runs away, but the woman will find him no matter what.
The gang then goes over the locations Scooby is known to visit from time to time. Freddie then tells everyone to split-up, but decides to stick together after Freddie forgets that Scooby isn't with them. Shaggy worries what will happen to his puppy, which causes Freddie to imagine Scooby running into various monsters, which further scares Shaggy. Velma then sees a trail Scooby left, and the gang proceeds to follow it. Freddie, however, realizes who did it, and tells the gang to follow him.
He interrogates Red, who tells him how he saw Scooby at the butcher shop. The gang then heads there next.
Mr. Porterhouse, explains that Scooby came by, and got a whole year worth of bones. Shaggy then breaks down in tears once again, but finds Scooby's favorite chew toy, along with other stuff he dropped, so the gang then follows it to find him.
Meanwhile, Scooby gets himself lost in an alley, and after getting his suitcase back from a pack of alley dogs, the woman finds him once again declaring his head is hers.
Scooby, however, escapes her again, and decides to go home, but can't figure out how to get back, which causes him to cry because he misses his friends.
The gang searches for Scooby in the same alley, where Daphne remembers when he tasted his first Scooby Snack. After the flashback ends, Shaggy finds Scooby's suitcase with a red paw-print on it. Freddie thinks it could be bloody paw-print which scares Shaggy. They're then attacked by the same dogs from before. Since Scooby isn't with them, Daphne calls for Jenkins, but her other butler, Dawson, shows up instead (he explains that Jenkins was out doing Daphne's shopping) and scares off the dogs for Daphne and the gang. Freddie then says they need to speed-up their search for their friend. Velma brings her skateboard, and they head off.
After getting thrown out of the market place, Scooby then falls into despair, which then turns to fear when the woman finds him again. After he lost her, he resumes to find his way home, while accidentally leaving his dog-tag behind.
After the gang searched the same area ten times, Freddie says all he saw was his dog-tag, which amazes the gang because Freddie finally found his first clue. They realize that they're on the right track, but not sure where to go, since Velma's computer is broken. But despite that, Velma calculated that Scooby went to the harbor.
Scooby finds himself lost, since it's so foggy. He runs into the woman again, who pursues him. Meanwhile, the gang runs into a shadowed figure in the fog, which Freddie believes it to be king of the eel people. However, it turns out to be Scooby hiding in an old box. The gang are overjoyed to have finally found him, and apologize for how they treated him, which Scooby forgives. Their reunion is cut short when the woman finds them, and decides she could use them all for her project.
After Velma and Scooby scared her off, Velma then gets an idea on how to stop her.
They pretend to give her a harbor cruise, and trap her in a chair, with a rubber tube. However, she escapes, and pursues them, when Velma finds a paintbrush she dropped, figuring out who she is. She has the gang cornered, with Scooby coming to help them after having enough of her. But Velma tells him that force isn't required, and that everyone's safe. She explains that she's Paula P. Casso, the famous artist. When Velma found the paintbrush she dropped, she realized that the paw-print on Scooby's suitcase was paint, not blood. Paula explains that she just wanted Scooby's head in her pictures, but when she saw how perfect it was, she got carried away. She apologized for scaring him, and asked if he could pose for a painting, which he forgives and accepts.
The next day, the gang throws Scooby a welcome home party, glad to have him back, and promises that they won't be too busy to play with him from now on. Upon seeing Paula's painting, it wasn't what they were expecting it to be. But Shaggy says paintings are no substitutes for his best friend, a pup named Scooby-Doo.
- Scooby-Doo Detective Agency (main story and flashback)
- Paula P. Casso (single appearance)(redeemed)
- Mole Men (single appearance)(no lines)(fantasy)
- Old woman (single appearance)(Dracula's disguise)(fantasy)
- Dracula (single appearance)(no lines)(fantasy)
- Two-headed Mummy Werewolf (single appearance)(no lines)(fantasy)
- Mr. Rogers
- Sugie Rogers
- Jenkins (flashback only)
- Bulldog (single appearance)
- The bulldog's crew (single appearance)(no lines)
- Dawson (single appearance)
- Market Place owner (single appearance)
- Scooby's letter
- Scooby's chewing toys
- Scooby's dogtag
- Tandem bicycle
- Velma's magnifying glass
- Dab Magazine
|Paula P. Casso||An innocent artist who wanted to make a portrait of Scooby-Doo.|
|Don Messick|| Scooby-Doo|
|Casey Kasem|| Shaggy Rogers|
|Christina Lange||Velma Dinkley|
|Kellie Martin||Daphne Blake|
|Carl Steven||Freddie Jones|
|Scott Menville||Red Herring|
|B.J. Ward||Sugie Rogers|
|Pat Carroll||Paula P. Casso|
Animation mistakes and/or technical glitches
- After Scooby crashed into the trash, his dog-tag disappeared and reappeared before he accidentally dropped it.
- And before he reunites with the gang, he was still wearing it.
Inconsistencies/continuity errors and/or goofs/oddities
- None known.
- A Pup Named Scooby-Doo: Volume 5 DVD released by Warner Home Video on January 9, 2007.
- A Pup Named Scooby-Doo: Complete 2nd, 3rd & 4th Seasons released by Warner Home Video on March 17, 2009.