Godzilla is throwing infantile tantrums and H.E.A.T. are growing worried about their ability to control him.

H.E.A.T. investigates a gigantic caterpillar-like mutation known as the Megapede, who is rampaging through the neighbor states of Illinois and Indiana. Godzilla is called upon to render assistance, but the Megapede sprays a form of poisonous foam, and also has poison producing spurs along its many legs, both of which serve to keep the Kaiju King at bay. The mega-insect finally climbs atop a building, forms a cocoon, and transforms into a huge winged insectoid creature with the habit of disrupting radar frequencies by rubbing its wings together, thus wreaking much havoc. H.E.A.T. concocts a poison neutralizing foam, which it spreads on the kaiju's wings, allowing Godzilla to attack and defeat the creature more easily.

As a result of an oil platform in the Gulf of Mexico exploding, a mutant seemingly composed of living fire emerges. As this creature goes on a rampage in the area looking for more combustible substances upon which to feed, H.E.A.T and Godzilla intervene. However, the creature grows larger and more powerful as a result of absorbing and feeding off of Godzilla's powerful incendiary breath.

In response to a sanitation workers' strike, a colony of petroleum-eating microbes, controlled by nanotechnology, are released to try to curb New York's garbage problem.

A new and deadly mutation, a plant-like creature known as Bacillus (who may have been inspired by Biollante), appears and begins wreaking havoc, prompting H.E.A.T. to call upon Godzilla. During the battle, Godzilla is seriously injured and rendered catatonic as the result of being injected with a highly dangerous form of mutated bacteria by Bacillus. In order to save their kaiju ally, Tatopoulos and Monique travel within Godzilla's body in order to carefully exterminate all of the mutant bacterium. Now fully healed, Godzilla attacks Bacillus anew, and eradicates the creature with his incendiary breath.

Cameron Winter returns to take yet another shot at H.E.A.T. and Godzilla, this time enlisting the aid of the three redneck, would-be-killers of the Big G from the previous episode ""Cat and Mouse,"" and equipping them with powerful machines of destruction (sometimes referred to as 'Battle Mechs'--another thank you to Doc Psy from Centropoholics:). Godzilla, H.E.A.T., and a military unit commanded by Major Hicks battle the machines and destroy them, and the three violent hicks are arrested.

H.E.A.T. are dispatched to aid investigation into the disappearance of a search party looking for oil in Antarctica.

In Miami, Godzilla, H.E.A.T., and Major Hicks battle Skeetera, a mutated bloodsucking mosquito-like insect who adapts the powers of the creatures she feeds on. As they attempt to contain the creature they are interrupted by the mutation rights fringe group known as S.C.A.L.E. (Servants of Creatures Arriving Late to Earth).

On the Arabian Peninsula, a team of archeologists led by Professor Abrim Kasam unearth an ancient statue of the flying lion Norzzug, the guardian of the ancient city of Amon-Ra. When restoration specialists spray the statue with an anti-oxidant solution, the iron-skinned creature suddenly comes to life.

H.E.A.T. investigates the legendary “Area 51” in Nevada and discovers its true secret is not alien landings, but giant mutated desert creatures created by decades of underground nuclear testing.

H.E.A.T. tackles a gigantic mutant shrew-like creature, which has somehow merged itself with an artificially generated, experimental tornado, enabling it to transform itself into a living vortex at will (Elsie wittily dubs the whirling beast 'The Shrewster'). In order to maintain its ultra-fast, whirlwind powers, the Shrewster is forced to rapidly consume three times its body weight per day, thus causing it to greedily devour every organic food source in its path, effectively making it an extremely dangerous menace. Because of its ability to transform itself into an organic tornado, Godzilla is unable to get at the beast, and Tatopoulos ends up trapped in the Shrewster's vortex. However, soon after becoming trapped, he activates a device that Craven crafted, which was designed to dissipate the vortex's cyclonic forces, and this succeeds.

Another new and dangerous mutant species appears on the scene, this time in the form of gigantic hummingbirds that attack planes flying over San Francisco. Worst of all, this mutant avian species is able to render themselves invisible via the hummingbird trait of flapping their wings faster than any other bird species in the world. As a result of their ability to cloak themselves so as to be invisible to the unaided eye, Godzilla is unable to see the creatures in order to attack them.

During its latest creature investigations, H.E.A.T. splits up into two teams, one of which investigates a group of mutant parasitic organisms in Florida, whereas the second group handles a case of a giant, mutated, and rapidly growing multi-tentacled fungi-like creature in Michigan.

H.E.A.T. are called to help the Central America Republic of Costo Rojo to deal with "El Gusano Gigante", a mutant worm that is devouring untold amounts of crops.

When a strange electrical creature known as the Crackler attacks seemingly random locations in Manhattan, the team investigate.

When Godzilla is accused of attacking New York, the military call in H.E.A.T. to help contain him. But Phillipe Roache has returned from France...with orders to terminate Godzilla.

After Godzilla battles robotic insects, the team encounter their creator: Cameron Winter, a powerful technology mogul and an old rival of Nick's from college.

The team are called to help a rescue mission for xenobiologist Alexander Preloran, who disappeared while on a mission to explore the Leviathan, an alien spacecraft buried at the bottom of the Pacific Ocean for 65 million years.

When villages in Mexico are attacked by a strange winged creature, ornithologist and Elsie's old fiancé Lawrence Cohen calls H.E.A.T. for help.

H.E.A.T. is charged by the Pentagon to investigate the growing population of spiders near an Army base in the Canary Islands.

The Techno-Sentient, an alien piece of technology, falls to Earth and begins to bond with all manner of human technology, growing to gargantuan proportions.

Elsie is suffering from a family problem of a personal nature, along the lines of sibling rivalry: her sister's wedding is soon to take place, and she is chagrined due to the disproportionate amount of attention and familial adoration that her sister has received in contrast to her. Further, she feels that her family has little respect for her choosen vocation, i.e., her activities with H.E.A.T. [that must be quite a hard family indeed to show a lack of appreciation for a daughter who has routinely risked life and limb for her planet by investigating and battling dangerous, life threatening giant monsters, and even helping to thwart an alien invasion! Her sister must truly be the world's most talented ass-kisser].

While tracking Godzilla to Fort Armstrong, New Mexico the team discover a gigantic mutated scorpion, called Ts-eh-GO by the locals, is on the rampage.

A mutant giant rat emerges from the sewers of Manhattan.

H.E.A.T. investigates the tropical island of Santa Marta in the wake of a devastating volcanic eruption. But what they find on the island is that, due to irradiated lava, a hideously mutated ecosystem has developed, including carnivorous plants and gigantic bees.