Other Voices is the twenty-fifth and twenty-sixth episode of the Beast Wars TV series.
In a flash of light, a power anomaly emerges from a wormhole above the planet and descends to the surface. The aliens have arrived.
Tarantulas is programming his stolen transwarp cell, when Blackarachnia pays him another visit. She tells him she can get them inside the Maximal base to steal a stasis pod. Megatron monitors the entire discussion between the two spiders and sends Waspinator to the location the aliens are anticipated to arrive at.
Rattrap and Airazor reach the site, which is a large circular plaza of stone, pulsing with energy and containing a stable energon crystal. When Airazor tries to scan it, it zaps her, blasts Rattrap away, and engulfs the entire site inside an organic dome-like structure with Airazor inside.
Airazor awakens inside the "nutty alien bungalow", where a garbled alien voice speaks to her. She assures the aliens she means them no harm, but they have no such compunctions and painfully scan her until she converts to beast mode. After the scan ends, they are left with one word of information: "Cybertron".
Outside, Waspinator arrives to "secure the area", but Rattrap drives him off with a vigorous bout of fisticuffs.
Optimus Primal arrives and surveys the situation. Rattrap's efforts to use a laser to cut through the dome structure are ineffective. Megatron then arrives with Terrorsaur and Scorponok. He mocks Optimus for thinking that simple laser could get through the structure, commenting that the aliens can "create energon itself". He then has Scorponok fire a "toxic sting" that eats through the structure. Primal and Rattrap venture inside; Rattrap drags the semi-conscious Airazor out, while Primal stays to confront the aliens. A series of whip-like metal tentacles ensnare him and lift him up into an agonizing scanning grid.
Tarantulas and Blackarachnia have made their way to the Maximal base, where Blackarachnia activates a device that creates a small opening in the shields. The spiders move in, unaware that they are being followed by Inferno, who notes that they're up to no good and develops his own entry by digging a tunnel below ground.
Rattrap pulls Airazor out through Scorponok's opening just before it self-seals, to find himself facing Predacon guns. The truce is over.
Optimus Primal's scan ends, and to address him, the aliens (having no form he could comprehend) take the form of a "figure of authority"—the head of Unicron. The aliens tell him that the Transformers have contaminated their experiment, which will be "sterilized". Primal pleads for a chance to fix the damage, and for the lives of the planet's native creatures, but the aliens are dismissive, citing greater dangers unknown to Primal. The conversation ends with the aliens activating a "termination sequence".
The alien construct begins to pulse with building energy. The distraction proves enough for Rattrap and Airazor to overpower the Predacons. With renewed urgency, Optimus Primal breaks his bonds and flies right through the dome; the Maximals beat a hasty retreat—as the dome bursts open, spewing a directed geyser of energy into the sky. The energy activates hidden systems on the second moon, burning away its earthen surface to reveal an endless grid of weapon-like emplacements that begin powering up. The moon itself begins to change its shape, and the alien energies cause the orbiting stasis pods to tumble out of orbit.
Rhinox observes all this at the Maximal base, taking measures to track what's happening even as the sensors begin to fritz out. Thus engaged, he doesn't see the spiders coming up behind him till it's too late. Dinobot is likewise gunned down in short order. Staring at Rhinox's displays, Blackarachnia wonders what they're looking at, to which Tarantulas replies: "The beginning... of the end."
Out on patrol, Cheetor and Tigatron stare in awe at "the light at the end of the world", as the alien machine continues powering up in space. Optimus Primal makes contact and orders them to return to base. Rattrap is pessimistic about their chances of survival, but Primal assures him that Rhinox will find a way for them to survive.
The alien bungalow finishes transferring power to the moon, and in a flash, the aliens depart: "Termination sequence engaged. Return to Nexus Zero."
Megatron and the Predacons observe this from their base. Confronted with a machine intended to destroy them, Megatron activates a special program and scans the Maximal base, locating the spiders and Inferno within.
Tarantulas is nearly finished converting a stored stasis pod into his escape ship. Blackarachnia observes that it's a little cramped for two... but, weapon drawn, she has no intention of sharing the ride. Inferno arrives just then, blasts her, and sets Tarantulas on fire, knocking him out. Back at the Predacon base, Megatron detects the aborted flow of data to the stasis pod ship and reacts with fury.
Inferno starts to examine Tarantulas's work, but is attacked by Blackarachnia, who eludes him with a display of gymnastics before blasting him with his own gun. Picking up Tarantulas's cyber-link goggles, she forms a link with the unconscious Tarantulas to obtain the data needed to finish the pod ship—but finds that staring into the abyss of the spider's mind means that it also stares back...
The Maximals arrive at base, alarmed to find the shields down. Inside, they find Rhinox and Dinobot cyber-webbed to the ceiling. Optimus Primal sends Rattrap and Airazor to bring in their unwelcome visitors.
Megatron observes the data flow resuming, just as the altered moon opens fire on the planet with a broad, blinding power ray. Optimus Primal charges the Maximal base's shields as the external temperature begins climbing and deduces that the aliens intend to ignite the energon deposits. Megatron notes that this will obliterate the entire planet, an incredibly ruthless strategy that he rather admires. He assures his panicked troops that Tarantulas will save them, albeit inadvertently.
Blackarachnia finishes the pod ship, only to be discovered and held at gunpoint by Rattrap and Airazor. With Rhinox still out of commission, Optimus Primal is beginning to despair, when Rattrap summons him to the stasis hold. Primal is impressed by the ship and immediately orders Blackarachnia to change the command codes to respond to him. He intends to fly the ship up to the Planet Buster and detonate the transwarp cell to destroy it. With little alternative, Blackarachnia complies.
Soon all is ready, and Optimus Primal has poignant parting words with his worried crew - at which point Blackarachnia comments on the Maximals' sentimentality and is knocked out by Airazor for it - before sealing the ship and launching it. Megatron scans the launch and notes with delight that Primal is flying the vessel. Primal soon reaches the Planet Buster, starts the ignition sequence, and gives the order to blow the hatch seals. But the hatch is sealed and locked! Megatron appears on his comm screen to gloat that he'd come up with exactly the same plan—only in his version of events, the ship's pilot goes "up with the ship". As the timer counts down to zero, the Maximals frantically wait for Optimus Primal to make his escape. Primal pounds on the sealed hatch, to no avail. As the Maximals wonder what is going on, Blackarachnia tells them it's too late... in Tarantulas's voice.
The transwarp cell explodes, and high above the planet, the Planet Buster is annihilated... along with the pod ship and Optimus Primal.