After a prologue that introduces Mystery Machine kids Shaggy (Matthew Lillard), Daphne (Sarah Michelle Gellar), Fred (Freddie Prinze Jr.), and Velma (Linda Cardellini) solving their latest crime, only to break up after Fred once again takes all of the credit, the story switches forward in time two years. Shaggy and his faithful, talking dog, Scooby-Doo (voiced by Scott Innes), are invited to travel to Spooky Island, an amusement park where its partying, heavily teenaged customers are all mysteriously leaving as emotionless zombies. While at the airport, they reunite at the with their old friends. Daphne, fed up with just being the damsel-in-distress, is determined to solve the case herself this time, while Velma, also tired of constantly being pushed into the background, longs for her moment in the spotlight. Once there, however, they find that four heads (and a very smart pup) are better than one when it comes to cracking any big mystery.

The motion picture the actors and director, Raja Gosnell (2000's "Big Momma's House"), set out to make has been widely noted as not being the one that has ended up onscreen. Clever allusions to Shaggy's stoner ways, Velma's questionable sexual orientation, and Daphne and Fred's steamy romance have all but been completely stripped out of what is now a lame family film that takes no chances nor goes out of its way to be even slightly imaginative.

At the very least, the majority of the foursome have their well-known characters down pat. The usually unctuous Matthew Lillard (2001's "Thirteen Ghosts") has finally found a role he was born to play. His Shaggy, from his appearance to the squealing voice, is such an absolute dead-ringer for his animated counterpart that it's almost eerie. Likewise, Linda Cardellini (2001's "Legally Blonde") is the perfect choice to play the book-smart, eternally turtlenecked Velma, and Sarah Michelle Gellar (1999's "Cruel Intentions") has some fun skewering her "Buffy"-style toughness as Daphne. The weak link, as usual, is Freddie Prinze Jr. (2001's "Summer Catch"), although it isn't entirely his fault this time. Fred is, by far, the most underwritten and bland of the group, so it doesn't help that the casting director went with someone as equally vapid to play him. As for the new CGI'd Scooby-Doo, it is obvious every step of the way that he is a computer image, although his friendship with Shaggy still manages to be endearing.

If the actors are good for the most part, as a group they are never believable as friends. Since every scene is related directly to the mystery, and the pacing never quits, no time is spent developing these characters as either individuals or people who even really share a strong bond. Precious few moments in which they are allowed to simply communicate with each other as people sneak into the proceedings.

The other missed opportunity comes in the form of the wasted production design, by Bill Boes (1999's "Sleepy Hollow"). Along with art directors Bill Booth, Donna Brown, Helen Gabrielle Gliniak, and Christian Wintter, Spooky Island is a creatively robust and sparkling visual triumph, but nothing is ever done to take advantage of its setting. Once Spooky Island is established in a glorious long shot, we never again, or rarely, see any of these rides and attractions again.

"Scooby-Doo" has its share of fun moments. A cameo by the excellent music group Sugar Ray is a welcome surprise, and an action scene set inside a haunted funhouse ride has an amiable amount of thrills. For each of these passing glimpses at what "Scooby-Doo" could have been, however, there are at least a dozen more stale ideas, including a totally unfunny farting contest between Shaggy and Scooby-Doo that comes out of nowhere. Such comedic blunders as this unveil the desperation on the part of director Raja Gosnell, who has trouble making any of it work. If "Scooby-Doo" is, indeed, a commercial success, let's hope that the studio pays more attention to quality and creative freedom, and spends less time worrying about dollar signs, before the sequel goes into production.