Toon Legends: The Fantastic Four vs. The Molecule Man (1967)

 It's been a while since we checked in with the Fantastic Four.

Hanna-Barbera's take on "The Mysterious Molecule Man" is similar to the character's actual origin, revealed four years earlier. A lab technician (guest star Henry Corden) is caught in an explosion, and transformed from a gray haired scientist into the dark haired Molecule Man, complete with now-pointed ears and lightning bolts imprinted on his face, though Alex Toth's design doesn't match Jack Kirby's original drawings from 1963.

Unfortunately, Molecule Man would not return to cartoons until The Marvel Super Hero Squad Show, some 40-odd years later.

Rating: B.