Double Jeopardy is the eighth episode of the Beast Wars TV series.
Dinobot and Optimus Primal explore one of the planet's frozen regions looking to retrieve the latest stasis pod. They find the pod overhead, hanging over the edge of a cliff, and protected by the three Predacon goons. While Terrorsaur and Scorponok bomb the Maximal duo, Waspinator grabs the pod to lift it back to the Predacon base. Primal sees the theft and flies after the bug, but is brought down by a shot in the back from Terrorsaur. With Primal downed, the Predacons scamper away.
At the Maximal base, Optimus Primal laments regarding the frequency of the Maximals being ambushed. Primal calls Rattrap into a private meeting, making it clear he suspects Rattrap has been feeding information to the Maximals' enemies. Rattrap denies this, and Cheetor and Rhinox can't believe it. As a test of loyalty, Rattrap is sent on a mission into one of the more dangerous sectors.
At the Predacon base, Tarantulas reveals the new Predacon made from the captured Maximal protoform: Blackarachnia. Afterwards, they use their radio to eavesdrop on Rattrap's radio reports on how Rattrap's mission is going. Hearing that the rodent is by himself, Terrorsaur is sent to destroy Rattrap.
Terrorsaur and Rattrap battle, and with Rattrap unable to hit his target, Terrorsaur is able to stand over his enemy, his gun right in Rattrap's face. Desperate for his own survival, Rattrap bargains his own loyalty to Terrorsaur and the Predacons, while the rest of the Maximals listen, astonished by the change.
Back at the Predacon base, Terrorsaur introduces his new underling and, with said underling's aid, overthrows Megatron (who is placed into the Predacon brig). Because he still can't be trusted, Rattrap is also imprisoned. The two captives are placed in cages and suspended over a flow of lava. Of course, Megatron has anticipated his own imprisonment and escapes with a few simple computer commands. Once Megatron is out of sight, Rattrap picks the lock on his own cage and jumps over the lava to freedom (barely).
Sneaking through the base, Rattrap follows another, actual rat. He passes by a Predacon computer console and discovers it contains a Maximal computer chip, explaining how they were able to listen to Maximal radio frequencies and anticipate the Maximals' movement. After removing the chip, he continues his sneaking, but activates a security alarm and is caught in a security web. He escapes, but Tarantulas follows Rattrap back to the suspended cages, compromising Rattrap's operation, or so he would be, were it not for Rattrap silencing the arachnid with a gun shot.
The Maximals begin an attack on the Pred base to retrieve Rattrap. With the other Predacons looking to him for leadership, Terrorsaur panics—even more so when Megatron pops up right next to him, free from his cage. But he deigns to give
Terrorsaur rope to hang himself follow Terrorsaur's leadership as the Predacons counter-attack. Rattrap is freed to help in the defense, and on Terrorsaur's order, he opens fire on Optimus Primal, scoring a direct hit on his former leader. After the two armies bounce off each other a bit, Megatron gives Rattrap the opportunity to destroy Dinobot, but Rattrap declines and shoots Terrorsaur instead, giving Dinobot the time to free himself by kicking out some of Megatron's teeth. The Maximals take Rattrap and retreat. With Terrorsaur's command shown to be a total frak-up, Megatron effortlessly resumes command of his forces and rubs in the defeat.
Back in the Axalon, Optimus Primal explains to his friends that the entire betrayal was a charade—a ploy to let Rattrap into the Predacon base and find out how the Predacons have been listening to the Maximals' radio communications.