|Scooby-Doo! The Mystery Begins|
|Distributed by||Warner Premiere|
|Directed by||Brian Levant|
|Produced by||Brian J. Gilbert
|Screenplay by||Daniel Altiere
by Joe Ruby & Ken Spears
|Starring||Frank Welker (voice)
|Music by||David Newman|
|Editing by||Eric Osmond|
|Original channel||Cartoon Network|
September 22, 2009 (DVD)
|Running time||81 minutes|
Scooby-Doo! The Mystery Begins (also known as Scooby-Doo 3 or Scooby-Doo 3: The Mystery Begins) is a 2009 American television film comedy fantasy and adventure film directed by Brian Levant, produced by Warner Premiere and distributed by Warner Home Video. The film was aired by Cartoon Network on September 13, 2009, the fortieth anniversary of the Hanna-Barbera character Scooby-Doo, and later released on September 22, 2009 on DVD and Blu-Ray. It is the third installment in the Scooby-Doo live-action film series, the film is a prequel which depicts how Scooby and the Mystery Inc. gang met and the events of their very first case.
The live-action cast features Nick Palatas as Shaggy, along with Robbie Amell as Fred, Hayley Kiyoko as Velma and Kate Melton as Daphne. Scooby-Doo was created using computer-generated imagery and his voice is provided by Frank Welker, who also was a cast member of the animated series, Scooby-Doo, Where Are You!, providing the voice of Fred.
The music is scored by Academy Award-nominee David Newman, who had previously scored the theatrical films Scooby-Doo (2002) and Scooby-Doo 2: Monsters Unleashed (2004). The film is dedicated to Lorena Gale, who died during production.
Its sequel, Scooby-Doo! Curse of the Lake Monster, was released on October 16, 2010.
In Coolsville, Ohio, four teenagers are involved in a fight on the school bus and are sent to detention. Norville "Shaggy" Rogers is a clumsy, nerdy outcast, who tried to smuggle his dog Scooby-Doo onto the bus; Fred Jones is quarterback of the football team; Velma Dinkley is a science geek; and Daphne Blake is in the drama club. They bond somewhat over a shared interest in mysteries, but quickly get on each other's nerves. While in the library for detention, two ghosts appear and chase them to the gym where a pep rally is going on. A third ghost, The Specter appears, causing the lights in the building to flicker. He starts telling everyone to leave. The stamp-collecting Principal Deedle decides to close the school, but Vice Principal Grimes deems it a prank and suspends the quartet.
The gang tries to clear their names by investigating the ghosts, which leads to Grimes expelling them. Further investigation, in disguise at the school, makes them think Grimes is their prime suspect. Searching at night at Grimes' house leads them to information about a time capsule. The ghosts attack again, and the teens are knocked out. The Specter, keeping Scooby and Grimes as prisoners, forces the gang to search underground for the time capsule. Unable to find the capsule, they trick the Specter into coming down to carry the capsule out of the hole, but the plan backfires when they try to lock him up in a flooded room, and the Specter acquires the capsule.
Stealing the capsule back, the gang uses a book of spells to banish the ghosts. Scooby manages to break free of his restraints and arrives just in time to subdue the Specter, who turns out to be Principal Deedle. The principal reveals that a stamp misprint was hidden within the time capsule, something that would have been worth a fortune. As the exposed Deedle is sent to prison for his actions, the group is publicly congratulated (and un-expelled) by Grimes (who becomes the new Principal), and they decide to continue investigating strange doings.
- Kate Melton as Daphne Blake
- Hayley Kiyoko as Velma Dinkley
- Robbie Amell as Fred Jones
- Nick Palatas as Norville "Shaggy" Rogers
- Frank Welker provides the voice of Scooby-Doo
- Shawn Macdonald as Principal Deedle
- Garry Chalk as Vice Principal Grimes
- C. Ernst Harth as the Janitor
- Lorena Gale as the Librarian
- Daniel Riordan provides the voice of the Specter
Filming took place in Vancouver, British Columbia, Canada, including Templeton Secondary School from August 4, 2008. Cartoon Network's content advisor Rob Sorcher had said, “This contemporary take on Scooby-Doo will be an exciting movie event on Cartoon Network. This project is also an anchor component of our new push into movies, our great partnership with Warner Premiere and the overall expectation of Cartoon Network programming efforts.” 
Due to the success of Scooby-Doo! The Mystery Begins, a sequel went into development in October 2009. That same month, the cast from the first installment revealed that they were signed on for three films. Titled Scooby-Doo! Curse of the Lake Monster, principal photography commenced on March 15, 2010 in various locations around Southern California. The sequel aired on October 16, 2010 and was released on DVD in 2011.