Mystery Inc is the mystery solving team from Scooby-Doo.

The Scooby-Doo Project Edit

In a short based on the Blair Witch Project, the mystery gang (who thinks the Blair Witch is a man in a mask) decides to investigate the woods where the three filmmakers disappeared, and after a while the same thing happens to them. Strangely enough (as this is an official Scooby-Doo Movie) it was hinted at the end, that all of the members were killed by the Blair Witch.