Leonardo Watch, and his even skinnier, more skittish friend Mr. Riel, are weaklings in the macro world, constantly falling victim to shakedowns from bigger, stronger bullies. Leo acknowledges and accepts his low strength and fighting ability as simply the way things are.
Then he’s hit in the head by the baseball-sized vehicles of microbial hyperdoctor Li Gado, who lives in a suit the size of a flea. Gado is after his scientific counterpart Gemnemo (also a microbe) whose super-dangerous experimentation on “hyperaugmented accelerated cell division” will affect both micro and macro worlds. He’s counting on Leo to help him.
Riel, who is upset with himself for running when his friend was in trouble, is approached by Gemnemo, who offers to perform the hyperaugmentation procedure to make Riel stronger; someone to take seriously, even fear, rather than be taken advantage of.
It just so happens that Zapp is the first person to (politely) try to extract some pocket cash from post-procedure Riel, who reacts quite extremely, throwing Zapp out of the diner with such force he ricochets off several cars in the street.
Riel isn’t seeking the bullies who mugged him and Leo before, but they find him, and immediately wish they hadn’t; he beats the pulp out of them all, even the guy with fractal fists. When the police arrive, they find that any offensive action only makes Riel bigger, stronger…and harder to reason with.
Klaus, on a low-key mission escorting the SS-level symbiotic prisoner Dog Hummer/Deldro Brody to the art museum, gets wind of the police battle, but learn of Riel’s special ability to absorb all force used against him a bit too late, after Klaus tries to contain him with a blood grid barricade and Dog/Deldro perform the “Hundred Crack Fist of Me”.
The force of both Klaus’ defense and Dog/Deldro’s offense causes Riel to grow to kaiju scale. All of these big, huge hulking entities stalking around, smashing into each other, ruining the city around them…and it all started with a microscopic conflict between a microbial mad scientist and the valiant hyperdoctor working tirelessly to stop him.
The usual ways of dealing with threats won’t work here; they’ll only make things worse. The fate of both worlds may depend on weak ol’ Leo, Li Gado’s hastily constructed super-weapon (that looks like an elaborate plastic toy), and perhaps Sonic the monkey.