The kids head over to the Marine Institute, to help Velma's Aunt Thelma figure out where all the dolphins have disappeared too, but they discover a Headless Skateboarder, who tries to chase them away.
The gang go down to the Marine Institute at the beach where Velma's aunt Thelma said that her dolphins are disappearing. Scooby and Shaggy try to go surfing before getting to work, but a seaweed monster scares them. Red unmasks himself having followed them and gets what's coming to him by a lobster. Thelma greets them and leads them to the dolphins coral where only one named Skipper remains. Suddenly a Headless Skateboarder chases them inside the institute and they give him the slip. When they returned to the corral, Skipper has vanished. Scooby catches a scent, but finds a hot dog vender. Velma however, finds a jellybean and a trail of food. They follow it to a changing booth, and what appears to be the Headless Skateboarder shows up, but it turns out to be Red again. The beach patrol officer Sandy Sneakers warns him about causing trouble and tries to catch him after he insults her. Velma notices the back of her jeep contains scuba equipment. She leaves after failing to catch Red leaving tracks. A man named Gnarly Charlie shows up and is actually thankful the monster showed up because it scared away tourists so he could surf to his hearts content. They find him rather suspicious and notice a sign that points them to Al's Skateboard-O-Rama.
They meet Al, who tells them that since the monster showed up, business has been terrible. He claims to not know how to skateboard and that he just rents them. He gives them permission to look around and Scooby leads them to the shed. But before they could go inside, the Headless Skateboarder corners them.
Velma brings out a giant ramp and the monster jumps, but returns quickly. The gang goes over the safety check list for the chase and give the monster more skateboard gear for other kids and they easily escape. Freddie plans to go back tonight to investigate the shed.
They find many skateboard trophies who all say Fast-track Al, who is the same Al who owns the park. Velma did an analysis and they learn that Al used to be an international skateboard champ, but got involved with drugs. Furious, Freddie plans to question Al.
They interrogate Al, who admits that he can skateboard, but then got involved with the wrong people and his mistakes got him sent to prison and he opened the park when he got out, but the monster showed up. They assured Al they'll stop the monster.
They find something in the bushes and Red Herring emerges from within. He tells them that Sandy wouldn't stop chasing him and wants to hire them to help clear his name. Freddie refuses until Red offers them half-price.
The next day, Velma says that the best place to look for clues is underwater. They gather scuba gear and headed out to sea.
They find an underwater cave and the Headless Skateboarder shows up and an underwater chase begins.
They lose the monster and find the missing dolphins and Skipper in the cave. They also find devices used to control the dolphins and the pouches on their backs carry drugs. Freddie finds a stairway to the surface and Velma gets an idea to capture the monster.
They inform Al that they're closing in on the monster and get his permission to check on the shed for more clues. Shaggy and Scooby get chased by the monster and Freddie and the others wait from the judges tower to drop a harness to control the monster. Unfortunately, Scooby gets on a skateboard, crashes into the tower sending the others down, gets the harness on himself, and starts bouncing uncontrollably. He ends up catching the monster in a net and finds a speaker inside the head, which explains how it was talking. The first suspect was Sandy Sneakers, as tire tracks from her jeep were at the same places the monster showed up. The second suspect was Gnarly Charlie, who thought the Marine institute made the beach too crowded. Freddie suspects that it has to be Red Herring, only for Red to show up to remind Freddie that he's paying him to prove his innocence. Velma says that there's one more suspect and unmasks the monster, revealing it to be Al. Al is part of a drug-smuggling gang that was using the stolen dolphins to transport their drugs. He used the monster disguise to scare people away so no one would see the dolphins and he lied about not being able to skateboard to throw suspicion off of him. The stairway in the cave led directly to Al's shed. Sandy comes in to take Al away, but Velma doesn't agree. Gnarly comes in and plans to take them both to FBI headquarters revealing that Sandy was working with Al and Gnarly Charlie was an undercover FBI agent.
The dolphins are returned to the corral and Red refuses to pay them, until Scooby knocks him into the corral and the dolphins fling him around.
- Headless Skateboarder (single appearance)(Al's disguise)
- Al (single appearance)
- Sandy Sneakers (single appearance)
- Seaweed Monster (single appearance)(no lines)(Red Herring's disguise)
- Skipper (single appearance)(no lines)
- Beach vendor (single appearance)
- Hotdog vendor (single appearance)(no lines)
- Freddie's bicycle
- Velma's bicycle
- Daphne's bicycle
- Shaggy's bicycle
- Vacuum cleaner
- Sandy Sneakers's Jeep
|Sandy Sneakers||Tire tracks from her jeep where at all the places were the skateboarder showed up.|
|Gnarly Charlie||He didn't like the Marine Institute because it attracted tourists that cluttered the beach.|
|Al||He was known to be involved with drugs in the past, though he claimed he had reformed.|
|Red Herring||As always.|
| Al as the Headless Skateboarder|
|To smuggle drugs.|
|Casey Kasem||Shaggy Rogers|
|Christina Lange||Velma Dinkley|
|Kellie Martin||Daphne Blake|
|Carl Steven||Freddie Jones|
|Scott Menville||Red Herring|
|Jerry Houser|| Al|
|Jackie Joseph||Aunt Thelma|
- This is probably the first time in the Scooby-Doo franchise where an episode makes a reference to a real social issue: drugs. This was a national crisis during the 80's and many cartoons during that time had been discussing it. When this episode aired, Nancy Reagan's Just Say No campaign was prevalent; this campaign from the 1980s and early 1990s was part of the U.S. War on Drugs and it was used to discourage children from engaging in illegal recreational drug use.
- Because of this, in the UK, Cartoonito skips over this episode, although it does air the episode of Baby Looney Tunes, Who Said That?!, where Daffy learns a bad word.
- The title of the episode is a play on the main character's name: Scooby-Doo.
- When Daphne suspects Sandy Sneakers to be behind the case, she was right. However, this is one of the few episodes where multiple suspects are guilty. Also, she is one of the few suspects not to wear a monster costume.
- Disguises: Scooby and Shaggy disguised as mermaids.
- Traps: To put the remote-controlled collar on the Headless Skateboarder.
- Scooby Snack bribe: 1.
- "Zoinks" count:
- "Jinkies" count: 2.
Animation mistakes and/or technical glitches
- When Daphne and Velma are examining Al's trophies, Velma's lips are moving, but Daphne's voice is heard reading the inscription.
Inconstitencies/continuity errors and/or goofs/oddities
- In the beginning of the episode Red Herring gets pinched by a lobster after scaring Scooby and the gang. The lobster is bright red. Lobsters acquire their red color after being boiled. Live lobsters are actually a dark greenish-brown color.
- There is no explanation for the origin of the Headless Skateboarder. Presumably this was the first time such a villain appeared, and as such this would be the beginning (and end) of the Headless Skateboarder.
In other languages
|Greek||Η Εξαφάνιση των Δελφινιών||The Disappearance of the Dolphins|
|Polish||Scooby Duduś||Scooby Dude|
- A Pup Named Scooby-Doo: Volume 3 DVD released by Warner Home Video on July 18, 2006.
- A Pup Named Scooby-Doo: Complete 1st Season DVD set released by Warner Home Video on March 18, 2008.
- Scooby-Doo! 13 Spooky Tales: Surf's Up, Scooby-Doo! DVD set released by Warner Home Video on May 5, 2015.
Shaggy: (narration) Like, Velma got a call one morning, and the next thing we knew, the Scooby-Doo Detective Agency were on its way to the beach.
Freddie: Okay, Red, time to pay up.
|Previous episode:||Series:||Next episode:|
|Now Museum, Now You Don't|| A Pup Named Scooby-Doo|
|Ghost Who's Coming to Dinner|