1974, the school (Don't have a name for it! Coolsville High? No.) is up against their rival high school. The opposing star quarterback is star Mark Gravenstine, he's currently being scouted to play pro, nothing is wrong in his life.
But then, during the big game, his leg is broken and the doctors tell him he'll never play pro. He swears vengeance on the football team that ruined his life. But before he could he killed himself.
Today, Right as the high school is having their best season to date, Football players start vanishing from the locker room. When players had disappeared before, it was assumed they had run away. But this time, blood was found, then a body.
Freddy Jones, captain of the debate team and all around swell guy, decides to look into this, he recruits his girlfriend, Daphne, and his friend Shaggy to tag along, on their way to the locker room, they meet, shy bookworm, Velma studying in the library. Freddy convinces her to join up because "we could use another brain!" Freddy decides they should all split up and search a different part of the locker room. Velma, still not so sure skulking around at night is the best way to do this runs into the ghost of Mark Gravenstine! A chase ensues and the gang only barely gets away with their lives. The next time they investigate, Shaggy brings along his big ol' dog Scooby-Doo.
Velma and Freddy scour the library and hall of records, and figure out that Gravenstine never died, he changed his name!
Well, as it turns out Gravenstine had gotten himself hired as a janitor at the school and had been 'removing' football players that were getting in the way of his alma matter winning, disguised as the ghost of himself.
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