Feature-length animated adventure following Scooby-Doo (voice of Frank Welker) and the Mystery Incorporated gang as they try to solve another ghostly mystery. On a visit to the Crazy Q Dude Ranch the gang learn it was once haunted by the ghost of villainous cowboy Dapper Jack, who, it turns out, looks just like Shaggy (Matthew Lillard), as the pair are distantly related. When Dapper Jack returns once again to terrorise the ranch, the gang agrees to help stop him so that ranch owner Tawny Rogers (Melissa Villasenor) doesn't have to sell up and leave. Will they be able to solve the mystery and trap the outlaw before he drives everyone out of the ranch?