A Plague of Insecticons

The ravenous Insecticons arrive on Earth, devouring everything in their path and forcing Autobots and Decepticons into an uneasy reckoning.

On the island of Bali, there is a heavily-forested swamp through which people rarely travel. It is the Demon Swamp, and in that swamp lie monsters who appear to be enormous insects. But they are not insects, they are Shrapnel, Bombshell, and Kickback, and they are robots in disguise. They are driven by a single, unrelenting desire: food. Attacking a trio of boats, the insects feed on the grain, but quickly become interested in the reports of a farm. At the Autobot base, Spike overhears the reports of "robot insects", and a team is taken aboard Skyfire to investigate while Sparkplug remains to alert Optimus Prime and the rest of the Autobots.

However, Laserbeak comes across the transmissions, and Megatron is intrigued. He takes a group of Decepticons to Demon Swamp, where Soundwave dispatches Ravage to locate the robots' lair. The Decepticons discover that the lair is not a hollowed-out rock, as it appears, but an escape pod ejected from the Decepticon cruiser that brought them to Earth. Thundercracker realizes what Megatron has already figured out: The robot insects are Decepticons who have been modified to assume insect modes—Insecticons, if you will.

Meanwhile, Optimus Prime is leading the rest of the Autobots to the farm, but they are blocked by a local festival. Sideswipe leads the Autobots down a shortcut...which turns out to be a dead end. Refusing to admit defeat, Sideswipe decides to drill his way through the solid rock. Arriving at the farm the Insecticons are attacking, Bumblebee, Windcharger, and Brawn attack, only to discover that the Insecticons possess some impressive weapons systems. Worse, they can make clones of themselves by using shells and scrap metal. Overwhelmed, the Autobots take cover amid the crops, but Shrapnel releases a fragmentation grenade which cuts the crops down to size. Finally, Megatron and the Decepticons arrive. The Autobots realize they're in over their heads, but Skyfire has been damaged and cannot transform. Shrapnel finds something familiar about the Decepticons, and when Megatron explains that they came from Decepticon science, Shrapnel extends his hand in friendship...an alliance which will be solidified by destroying the Autobots at the farm.

Elsewhere, Sideswipe is getting nowhere slowly with his drilling, so Optimus Prime decides on a simpler tactic and drives right through the rock wall. Coming up on the farm just in time, Sideswipe and Sunstreaker tackle the Decepticons, who withdraw to a nearby oil refinery to recharge before they destroy the Autobots. During the respite, Wheeljack repairs Skyfire, who follows them in the air while the Autobots follow from the ground. The Insecticons attack Skyfire, and Wheeljack goes to help but is knocked out of the air by Kickback. Shrapnel takes control of Sunstreaker and Sideswipe, causing them to drive toward the Autobots, but Trailbreaker disrupts Shrapnel's control with his force field. Optimus throws Brawn at Shrapnel, but Kickback knocks him off. Fortunately, Skyfire is able to catch Brawn.

At the refinery, the Decepticons are busy making some energon cubes. Megatron offers the Insecticons a tanker filled to the brim, and the trio gorge themselves. Unfortunately, it also causes the oil to leak into the ocean. As the Autobots arrive, the Decepticons force them to take some cover. Shrapnel uses a shrapnel grenade to knock Optimus, Brawn, and Wheeljack into the ocean, where the Autobot leader warns that the oil could ignite. On cue, Thundercracker lights the oil on fire, only for the Autobots to knock him into the flaming water. Before the ship goes kaboom, Ironhide is able to douse the flames. However, storm clouds appear overhead, and Shrapnel uses them as a means to fire electricity at the Autobots. Spike realizes that the rubber in their tires will serve as insulation. Some Autobots go to vehicle mode, while others stand on them, neutralizing Shrapnel's abilities. In addition, Trailbreaker uses his force field to neutralize Shrapnel's control over the clones, causing them to go to pieces.

Megatron realizes that he's losing, so the Decepticon leader employs a time-honored strategy: "If I can't have it, no one can." Megatron sets the tanker on fire and pushes it toward the refinery. However, Optimus pushes the tanker underwater, and Megatron with it. Rising to the surface, Megatron prepares to blast Bumblebee and Spike, only for Optimus Prime to throw the tanker through the air at Megatron.

The Insecticons observe the deteriorating situation and decide to cut their losses. They begin to feed off the energon, but Megatron, his rage overwhelming his common sense, orders the Decepticons to attack the Insecticons. As the Insecticons flee with the Decepticons in pursuit, the Autobots claim victory. Optimus Prime still worries that the Insecticons will inevitably be drawn back towards the Decepticons, but when and if that happens, the Autobots will be ready.

—Windcharger is hit by an Insecticon blast.

—Skyfire, after getting his ass handed to him by an army of Insecticon clones.

—Brawn, showing he is an optimist, even in the worst situations.

—Skyfire comes up with something else for Wheeljack to invent.

—Shrapnel zaps Wheeljack.