Johnny in the Valley of the Giants

Johnny and a group of boys (Boy Scouts, perhaps) are camping out one night when they discover a spooky old castle. The owner of the castle has a shrinking machine, and he uses it to shrink the boys to the size of flies. Johnny escapes the castle and winds up in a beehive, where he gallantly defends the hive and is knighted by the Queen Bee. He then mobilizes the bees and other forest animals to attack the castle and rescue his friends. (Troma Entertainment)