(Top-Notch Comics 008, 1940)
After Harley Hudson perfects his muscular coordination technique and becomes the Firefly after two years of hard study, his first order of business is to move to New York City to find a job, because it's hard to fight crime on an empty stomach. Plus NYC is the place to be for super-heroics and super-crime. Case in point: the very first job ad that Hudson follows up on turns out to be criminal scientist Dr Dread (unnamed in his first appearance), who is acquiring experimental subjects with a simple notice in the papes.
Dread's experiments involve "mechanical brains" that somehow mutate their recipients into huge goblinoid creatures (called the Green Men even though they trend more grey-brown) once implanted - the details are fuzzy at best. He believes that Hudson (and reporter Joan Burton, also unnamed this ish) have the fortitude necessary to be the Adam and Eve of an improved Green Man species, with which Dr Dread will take over the world.
Luckily for Hudson/ unluckily for Dr Dread, the operation requires a period of complete darkness, allowing Harley to switch to his Firefly persona and begin beating some Green Man ass.
At this point, it's all over for Dr Dread - even the late-game addition of a mutated primate named Mongo does little to slow down the muscularly coordinated hero. Mongo goes out the window and the world is poorer for it.
Indications at the end of that first Dr Dread story are that he escapes, but Thrilling Comics 009 finds him about to be executed for his crimes. After he is electrocuted, his body is collected by a henchman - presumably Selig, his assistant from his first appearance and also a rare example of a mad scientist's assistant who doesn't end up dead by the end of the adventure.
Somewhat coincidentally, not long after Selig has hauled Dr Dread's corpse away than the district attorney who prosecuted him is attacked and killed by a couple of walking corpses, who then spontaneously deanimate, leaving both a mess and a mystery in the middle of what was formerly a nice restaurant.
The mystery is solved when Joan Burton is kidnapped by some more walking corpses and spirited away to a remote castle, where she finds Dr Dread, alive and well. It turns out that he merely drank a potion that made him immune to being electrocuted - if the comic book justice system wants to keep on using capital punishment, they really are going to have to start treating villains like a superstitious peasant treats a suspected vampire: beheading the corpse is a minimum requirement to keep those suckers in the ground.
Dr Dread is of course using his walking corpses to get revenge on those responsible for his capture and sentencing: the District Attorney (RIP), Joan, the Firefly and Judge Grayson. To that end, he locks Joan and the Firefly in a room with some kill-crazy corpses and then leaves to do something else, in classic super-villain deathtrap fashion.
The Firefly makes use of his track and field experience to pole vault himself and Joan out of this sticky situation, leaving the kill-crazed corpses with nobody to murder. Thus, when Dr Dread comes back to admire his handiwork he instead finds himself as the target of their attack. He doesn't make it.
JUDGE AND JURY REVENGE KILLER SCORE: 1/4