It's Mean, It's Green, It's the Mystery Machine is episode number 5 in the What's New Scooby Doo series. Spoiler Alert - episode guide and details of It's Mean, It's Green, It's the Mystery Machine are below.
The Mystery Machine has gone rouge! Shaggy and Scooby see it suddenly come to live and driving down the street. They quickly realize that NO ONE is behind the wheel. Cue the spooky music and the van turning around causing them to run for their lives.
Of course, the rest of the gang does not believe them. But later while Fred is driving, the Mystery Machine suddenly takes over the driving from Fred and races towards a head-on collision with a barrier. Luckily, Scooby remembers and releases an emergency stop parachute that Fred has installed.
The gang takes the van to their mechanic, Murph, who seems less interested in fixing the Mystery Machine and more interested in buying it. While this is going on, the van comes to life again and drives away, leaving a trail of oil. The gang follows the trail, like breadcrumbs, to a strange house. Knocking on the door, they meet Mrs. Dinwidde, mother of the Mystery Kids, Andy and Mandy Dinwiddie. A musical group that mom really wants to reintroduce to the music world. The gang also meet Andy's and Mandy's brother, Randy, who is working an an unspecified science project. They also learn that the Mystery Machine was owned by the Mystery Kids before it was owned by Fred.
Apparently, the Mystery Kids are missing their pianist who stormed of the stage one night. He's been missing since then and everyone thinks he is in "Rock and Roll Heaven."
The gang head into the city followed by the Mystery Machine. Eventually it attacks them, glowing eerie green lights and playing spooky music riffs. After ditching the Mystery Machine, the gang runs into Randy at the University. He explains that he's working with machines allowing him to control anything wirelessly.
The gang returns to Murph for help. Not finding Murph, they do find back room filled with Mystery Kids memorabilia. After watching a one of the films about Flash Flannigan and how a flower mysteriously appears on his gravestone. The gang decide to investigate the graveyard.
There they find Andy and Mandy kneeling next to the grave of their friend. The Mystery Machine suddenly arrives and starts chasing the gang, until it finally nets Shaggy with the doors. The police eventually stop the rouge Mystery Machine.
While in police custody with the police, the gang head to see the Mystery Kids prepare for a show. Murph happens to be there. Velma decides to hold a seance and Daphne improvises by pretending to call to Flash in the spirit world. The Mystery Machine coincidentally arrives, to Daphne's surprise. Velma has a plan ready though and drops a lead-lined cover over the van, meaning that wireless control doesn't work. When they pull back the table cloth, the culprit turns out to be Susan Dinwiddie who had been controlling the machine using a wireless control, which she learned while helping Randy with his homework.
- The Monster: Haunted Mystery Machine
- The Villain: Susan Dinwidde
- Why: She wanted to get her kids back to music stardom and getting their old van back.