The "creeping unknown" in this Jonny Quest episode is a malevolent, mutated plant monster, headquartered in a dismal swamp. Suspected of causing the disappearances of several innocent humans, the monster is targetted for neutralization by the Quest Team. They'd better hurry; the plant's victims have turned into plants themselves, every bit as dangerous and terrifying as the "original." "The Creeping Unknown" first aired on December 14, 1986 as part of the syndicated "Funtastic World of Hanna-Barbera" weekend package. ~ Hal Erickson, Rovi