The gang have to connect the dots between a ghost truck haunting a highway and the town's recently missing crystal doorknobs. During the investigation, the gang also have to contend with helping Mayor Jones get reelected, and Daphne tries to keep her date with Rung Ladderton a secret from Fred, who couldn't be happier for her when he does find out.
In the night, a speeding teen driver is warned by a policeman not to drive too quickly. Suddenly, a large truck rushes by. The policeman gets on his bike and follows the truck along the cliff road. He manages to drive right up to the front window so that he could tell the driver to slow down, but he realises that no one is driving the vehicle. He is run off the road, his bike splashes into the sea water and he's shown to have grabbed a branch, hanging off the cliffside.
Meanwhile, Fred and the gang are helping Mayor Jones to win the reelection against George Avocados. Velma said that Daphne would've loved to help, but had a prior engagement; at Daphne's, her parents are keen for her to meet up with Rung Ladderton, who is a rich boy and heir to his father's ladder company. When printing out pamphlets for Fred's father, Scooby accidentally overloads the copying machine, and ink explodes over George Avocados. Mayor Jones explain that George's father Theodore Avocado's used to be mayor, until he stole a diamond from the bank. Theodore went to prison but the diamond was never found, and George has claimed his father's innocence ever since.
Driving home, the gang in the Mystery Machine are met by the Ghost Truck that has suddenly appeared behind them and is trying to push them off the cliff. It succeeds, but the gang are lucky to find that they land on the lower road. The truck comes again and they are forced to enter a tunnel with the truck gaining on them. Fred manages to steer the wheel so that they reach the edge of the road and away from the truck.
Sheriff Bronson Stone arrives to take down details. He claims that the Ghost truck will be a good tourist attraction. Daphne receives a call from Rung Ladderton about having dinner at the Bloody Stake. To Daphne's astonishment and dismay, Fred seems all right with it.
Returning to Mayor Jones' office, the gang discover that door knobs are missing around the city. Velma points out that George Avocados could use this as a turning point for people to turn to him as a better leader. They head to the Clam Cabin and realise that the door knobs are gone there and Skipper Shelton is still inside.
Daphne awaits Rung in The Bloody Stake, who arrives very late and rudely says that Daphne should pay because he'd forgotten his wallet. Fred compliments him on his ascot and they swap. Daphne can't believe this. Fred has now set up a trap in the town hall for the Ghost Truck and they go looking for it on the cliffs by following George Avocados, whom they suspect. Avocados' car disappears and they land straight in front of the Ghost Truck, but it hasn't been turned on. They decide to look closer, but it then turns on and they are forced to be chased again. This time, Fred turns behind a large rock and turns his headlights off. The Ghost Truck just goes straight by.
The gang now investigate the cliffs as this seems the perfect place for the Ghost Truck to hide. They find a secret cabin and piled high inside are the door knobs of Crystal Cove. They also found a journal belonging to Theodore Avocado's, George's father who stole and hid the diamond. The Ghost Truck appears down the cave and the gang rush back to the Mystery Machine. This time they head into the city, with Fred's mind on the trap he'd set. After a bumpy ride on top of one of the house's roofs, they enter the town hall and Scooby starts the trap. The Ghost Truck is thrown to the ground by a large spatula.
Mayor Jones appears after hearing a lot of noise. Rung Ladderton crawls from out of the truck. He performed as the Ghost Trucker so that he was able to secretly transport the door knobs to his cavern in the cliffs. He was desperate to find the crystal door knob that Avocados' father had replaced with a door knob.
Mayor Jones apologizes for losing a very popular tourist attraction, but makes up for it by announcing that he is staying as the mayor. He receives a large cheer.
- Mystery Incorporated
- Mayor Fred Jones, Sr.
- George Avocados (first appearance)
- Nan Blake
- Barty Blake
- Sheriff Bronson Stone
- Motorcycle cop (single appearance)
- Pulled over teen driver (1st speaking role)
- Shark (single appearance)(no lines)
- Skipper Shelton (first appearance)(cameo)
- Angie Dinkley (mentioned)
- Dale Dinkley (mentioned)
- Angel Dynamite
- Miss Vampire Waitress (first appearance)(no lines)
- Mr. E (voice only)
- Theodore Avocados (single appearance)(no lines)(flashback only)(deceased)
- Deputy (no lines)
- Crystal Cove tourist (Don Knotts lookalike)
- Crystal Cove
- Mayor Jones's campaign pamphlets
- Rung Ladderton's pendant
- Daphne's locket
- Sheriff Stone's pen
- Sheriff Stone's notepad
- Shark tank
- Fred's ascot
- Daphne's cellphone
- Rung Ladderton's cellphone
- Fred's smartphone
- Velma's cellphone
- Velma's binoculars
- Finger fries
- Rung Ladderton's wristwatch
- Rung Ladderton's ascot
- Daphne's purse
- Gang's flashlights
- Crystal doorknobs
- Theodore Avocados's journal
- Scooby Snack
- Diamond stolen by Theodore Avocados (flashback only)
- Speeding teen's car
- Cop's motorcycle
- Rung Ladderton's truck
- The Mystery Machine
- Sheriff Stone's police car
- George Avocados's car
- Pick-up truck
|George Avocados||To win the election for mayor.|
|Rung Ladderton, driver of the Ghost Truck||To find a stolen diamond hidden as a doorknob.|
- A "rig" is another word for "truck" in North America, Australia, and New Zealand.
- When Daphne sews Freddy's new ascot, she hums the The New Scooby-Doo Movies theme song.
- Disguises: None.
- "Zoinks" count: 1.
- "Jeepers" count: 0.
- "Jinkies" count: 1.
- "Hold the phone" count: 0.
- A road battle between a truck and a smaller car is the theme of the 1971 TV movie, Duel.
- The jumping gimmick on the Mystery Machine is like Speed Racer's Mach Five.
Animation mistakes and/or technical glitches
- During the final chase scene, the color of the ascot Fred is wearing switches from Rung Ladderton's purple to Fred's usual orange, and back again several times.
Inconsistencies/continuity errors and/or goofs/oddities
- The next episode reveals that the Clam Cabin serves from the outside.
- At the press conference following the unmasking, Mayor Jones tells the crowd that the kids have recovered the missing diamond that was stolen by Theodore Avocados. However, in the season 2 episode, Theater of Doom, it is revealed that the diamond was at the Burlington Library the whole time, and is only recovered then.
In other languages
|Spanish (Latin America)||El Fantasma de la Carretera||The Ghost of the Road|
|Spanish (Spain)||El Secreto del Fantasma sobre Ruedas||The Secret of the Ghost on Wheels|
|Italian||II Segreto Del Camion Fantasma||The Secret of the Ghost Truck|
|French||Le Mystère du camion fantôme||The Mystery of the Ghost Truck|
|Portuguese||O Segredo do Caminhão Fantasma||The Secret of the Ghost Truck|
|Hungarian||A Száguldó szellem titka||The Secret of the Speedy Ghost|
|Greek||Το Μυστικό της Νταλίκας Φάντασμα||The Secret of the Ghost Truck|
- Scooby-Doo! Mystery Incorporated: Season One, Volume 1 DVD released by Warner Home Video on January 25, 2011.
- Scooby-Doo! Mystery Incorporated: Volume One DVD released by Warner Home Video on August 29, 2011.
- Scooby-Doo! Mystery Incorporated: The Complete Season 1 DVD set released by Warner Home Video on October 8, 2013.
- Scooby-Doo! Mystères associés: L'intégrale de la saison 1 (Scooby-Doo! Mystery Incorporated: The entirety of season 1) DVD set released by Warner Home Video on October 3, 2012.
- Scooby-Doo! and WWE: Curse of the Speed Demon DVD released by Warner Home Video on Augest 9, 2016
|Previous episode:||Series:||Next episode:|
|The Creeping Creatures|| Scooby-Doo! Mystery Incorporated|
|Revenge of the Man Crab|