Four of the Rescue Rangers (the only exception being Gadget) are at the police station on the lookout for cases. But Chip is the only one actually paying attention; Zipper is taking a nap and Monty is showing Dale a few tricks with static electricity. Zipper is none too pleased at being used by Monty to demonstrate his tricks and neither is Chip when, moments later, Dale tries the same trick on him.
As he tries to get Chip to relax, Monty gets a whiff of the cheese in Spinelli's sandwich (anyone who's reasonably familiar with the series will be nodding knowingly at this point). Anyway, Monty swipes the cheese just as his friends intercept him and pull him into an in-tray. Moments later, they hear Spinelli (who has just been on the phone about some bizarre lightning strikes) talking to a girl named Mandy.
Mandy's kitten, Spunky, is missing. Spinelli says runaway kittens aren't a police matter but promises that he will have his men keep an eye out. Chip decides this is a case for the Rangers and, taking the picture of Spunky that Mandy left at the station with them, they head out onto the roof. There, they use catapults made out of mousetraps and tea-strainers to fly across the street to Ranger Headquarters.
Chip tells Monty and Dale to show Spunky's picture round Cat Alley, while he and Gadget take the Ranger Plane (which Gadget has just finished repairing) and follow Mandy. At Mandy's house, the two rodents find the windowsill scored with clawmarks and the tracks of some unidentified animal on the ground outside.
At Cat Alley, Monty and Dale find the place thronged with mice, one of whom tells them that all the cats disappeared two nights earlier. Monty says that, in order to solve this, they need to "think like a cat". Dale, however, goes one better and suggests that they "be a cat". This involves them building a "cat" out of scraps of cloth and pieces of wood, its limbs powered from within by the rodents.
Suddenly, a robot bulldog appears and starts chasing after the "cat", just as Chip, Gadget and Zipper arrive in the Ranger Plane. The bulldog has hold of the "cat's" tail as Monty and Dale try to escape by making the "cat" climb a telegraph pole - presently, they go shooting up in the air, only to plunge straight back down again. Dale and the "cat" land in the bulldog's open mouth, while Monty lands in a nearby bin. The latter climbs out and whacks the bulldog with a metal bar but only succeeds in giving himself an electric shock as the bulldog collapses in a heap - with Dale still inside. Luckily, the remaining Rangers appear with a screwdriver, which Zipper use to unscrew a panel in the bulldog's metal body.
Gadget fixes the bulldog (after a fashion) and she and the others stow away inside it as it heads back to wherever it came from. That proves to be Professor Nimnul's laboratory, which the Rangers find filled with caged cats. Seeing Nimnul coming, they duck into an empty cage as the bulldog and two others (which are undamaged) line up before him. Nimnul uses a remote control to activate some mechanical arms at the centre of the room and extract three terrified cats from the undamaged bulldogs. He then flies into a rage when he finds that the bulldog the Rangers rode in hasn't brought back any cats and we learn that he was the one behind the lightning strikes Spinelli mentioned earlier.
Zipper finds Spunky in one of the cages and flies back to report to the others. They free Spunky, lower him to the floor and prepare to leave. But Gadget says they have to free the other cats first, even though there is the "small matter" of getting all the cages open. Zipper drags Nimnul's remote control over and Dale presses several buttons at random, inadvertently activating the arms. One of these grabs Spunky by the scruff of his neck, while Chip and Dale seize hold of the kitten's paws. Then, as Chip, Dale and Spunky are deposited on another of the hands, scrubbing brushes descend on the three animals and start building up a charge of static electricity. Fortunately, Gadget manages to switch the device off.
Nimnul comes in and the Rangers and Spunky run for cover. But Nimnul catches Spunky and places him inside the damaged bulldog. Spunky escapes as Nimnul activates the arms, which start hauling the cats out of the cages. Then, as the scrubbing brushes build up static electricity in their fur, Nimnul prepares to fire off a lightning bolt. Before he can do so, however, Spunky sneaks up behind him and latches onto his rear with his claws. Startled, Nimnul drops his remote control and Chip and Dale race to catch it.
Chip and Dale crash into each other as the remote lands on top of them. Monty pulls it off them and a chase between the Rangers and the undamaged bulldogs begins. Eventually, with a little help from the arms, they manage to neutralise both robots. Meanwhile, the remaining bulldog is snapping at Nimnul, while Spunky continues to cling to the professor. Then, Spunky loses his grip and falls to the floor as Nimnul orders the bulldog to recapture the kitten. Fortunately, Spunky escapes and when, moments later, Nimnul is about to kill all the Rangers except Monty, he attacks him again.
The bulldog continues to snap at Nimnul and eventually catches him as Spunky jumps to safety. Then, as Nimnul vows to get revenge, the bulldog collapses and doesn't rise again. Moments later, Monty - who has been caught in a stampede of cats - rejoins his friends, saying that he hopes he never sees another cat again. He then sees Spunky and apologises as Spunky hugs him. The next morning, the Rangers drop Spunky off at Mandy's house and, as the kitten is reunited with his owner, we learn that Monty thinks cats belong "as far from him as possible".