Sledge's endgame begins to unfold, as mysterious eggs are spotted around the globe. A random electrician spots it, and calls in the museum staff, believing it to be a dinosaur egg. Tyler and the others arrive and take the egg back to the base, before heading to work. As it happens, Heckyl is there enjoying a last meal before the end of the world. The rangers quiz him on Sledge's plan, Heckyl informing them that the egg will hatch into a Greenzilla, and there were six in total scattered around the world. The rangers try to recruit him in stopping Sledge, as he is the only one who has knowledge of his plan, but Heckyl refuses, citing that contact with the Dark Energem has made him irredeemable. However, Shelby asks a poignant question to him: If he really was evil, why save them from Badussa and help defeat him?
The eggs start to hatch. Greenzillas appear and begin to wreck Hawaii, China, New York, London and Tokyo, causing widespread destruction and panic. The rangers split up and each man a Megazord to combat the kaijus, but only the Spino Megazord is capable of taking it head on without reinforcements. Kendall and Keeper monitor the battle from the base, coordinating the battles and sending extra chargers.
Up in orbit, Sledge is putting the final preparations for his wedding together. One item of note is Poisandra's wedding ring, which has the Dark Energem on it. While Poisandra assumes Snide is going to be upset at this gift, Sledge assures her that he's planning to dispatch Snide on Earth in the future, though unfortunately Snide secretly overhears. Sledge's wedding is interrupted by a dungeon rat and news that only five of the eggs have hatched. In response, Sledge dispatches Snide to the 6th egg's last known location to work out what happened. Needing a bargaining chip, Snide steals the Dark Energem and heads to Earth.
Heckyl's last day on Earth is an adrenaline fueled trip around America, base jumping in a canyon, enjoying thrills in an amusement park and even skydiving. However, it is news coverage of the rangers' battles against the Greenzillas that makes him question whether he was truly redeemable. It is the cry of a little girl amidst the chaos surrounding the Greenzilla panic that makes him act altruistically, and the gratitude from the girl's mother makes him remember why you should do good, not for rewards or recognition, but because it is right. He spots one of the escape pods heading towards the museum and rushes to intercept.
While the rangers battle the Greenzillas to mostly a stalemate, before the arrival of reinforcements, Snide infiltrates the museum, and breaks into the base. He destroys the crystal beds, preventing new Dino Chargers from being created, and readies his blade on Keeper, but Kendall steps in and duels Snide. She is outmatched however, and is overpowered, Snide taunting that there is nobody left to protect her. Heckyl disagrees, jumping in-between to defend the pair. He blasts Snide with lightning, causing the armored enemy to withdraw, and Heckyl tends to the two rather than chase after his dark half. Kendall and Heckyl join forces and chase after Snide, who is heading for the escape pod to flee the Earth, but Koda and Shelby destroy the pod before he gets there. Enraged, Snide fights the heroes head on, swatting them like flies and knocking them around. However, he is knocked back by the arrival of Zenowing, James and Philip, who hit him with a triple blast, knocking him back. Snide calls for a Magnabeam, but Sledge refuses, opting to let the rangers just kill him instead. Snide curses Sledge, and makes his last stand against Heckyl, the rangers and the Ultrazord. The combined energy blast obliterates Snide for good, but does nothing to the Dark Energem, to everyone's shock. Heckyl asks the rangers if he can aid them in destroying the Energem, and after consideration, the rangers accept his help.
Back on Sledge's ship, the wedding is finally complete, Sledge and Poisandra are now 'awfully' wedded monsters. However, to Sledge's shock, the Dark Energem is gone. Fury quickly figures that Snide must have stolen it, and by logical extension, Sledge deduces that the rangers probably have it now. So, he dispatches Fury to find it before the rangers destroy it, or his new wife will be wearing a brand new fur coat. Fury heads to Snide's last known location, the destroyed Greenzilla Egg, back in the Dino Base, where Keeper is still recovering from the ceiling cave in...
Tropes:
- 11th-Hour Ranger: Heckyl joins the Dino Charge Rangers in their fight against Sledge, but isn't technically a ranger. (Yet...)
- Character Death: Snide bites it, and about time too.
- Cliffhanger: Keeper is injured from the cave in and left in the Dino Base to recuperate while the rangers fight Snide, meaning there is nobody to protect him when Fury invades the base.
- Godzilla Threshold: In every other season to date, the rangers have never used the Megazord on a small opponent. Snide and the Dark Energem are that dangerous, they opt to hit him with the Ultrazord's Cannon, as well as blasts from both Heckyl and the other rangers. And while this annihilates Snide, it doesn't do a thing to the Dark Energem.
- Grand Finale: Part 3 of 4: Heckyl completes his turn and joins the rangers, Snide is killed, Sledge marries Poisandra, and the rangers possess the Dark Energem.
- Heel–Face Turn: Heckyl finally completes his, officially joining the rangers in their fight against Sledge and the Dark Energem.
- No Kill like Overkill: Snide is destroyed with a combined attack from the Ultrazord, six rangers, and Heckyl.
- No-Sell: The Dark Energem survives the above without even a scratch.
- Pass the Popcorn: The rest of the world is freaking out about the Greenzillas, but Heckyl? He is casually walking around eating cotton candy.
- Trash the Set: Snide wrecks the Dino Base, destroying the Charger beds and a lot of Kendall's tech.
- You Have Outlived Your Usefulness: Sledge turns down Snide's call for the Magnabeam, allowing the rangers to destroy him for good.
