प्लॉट

Two mice of the Rescue Aid Society search for a little girl kidnapped by unscrupulous treasure hunters.

When a bottle containing a plea for help from a little girl named Penny makes its way to the Rescue Aid Society, a mouse organization in the basement of the United Nations building dedicated to the rescue and well-being of anyone in need, it is up to the brave mouse Miss Bianca and her chosen partner, the shy janitor Bernard, to rescue the girl. Searching for clues at Penny's home at Morningside Orphanage in New York City, the two mice discover that the girl has been kidnapped by the evil pawn shop owner Madame Medusa and her companion Mr. Snoops. On the back of Orville the albatross, Miss Bianca and Bernard travel to the terrifyingly gloomy Devil's Bayou where they learn the shocking truth: the innocent young girl is being forced down into a dangerous, dark underground pirate's cave where she must find the Devil's Eye, the world's largest diamond and Madame Medusa's greatest obsession. Before returning safely home, Miss Bianca, Bernard, and Penny will have to combat Madame Medusa's two ferocious pet alligators Brutus and Nero with the help of Ellie Mae and Evinrude the dragonfly, as well as survive the raging tides inside the horrible pirate's cave.—Frederick Irizarry

When a little girl named Penny sends a bottle containing a written plea for help, Miss Bianaca, a Rescue Aid Society member and a representative of Hungary embarks on a mission with her new partner, Bernard, who is a janitor and dreams of being a member of the Rescue Aid Society. The two head to Morningside Orphanage to get some clues regarding Penny's disappearance. An elderly cat named Rufus reveals to Bianca and Bernard that Penny ran away and she was captured by a strange woman who is running a pawn shop. Bianca and Bernard go to Devil's Bayou in Louisiana to rescue Penny from Madame Medusa, who wants a priceless diamond that is worth millions of dollars. Along the way, Miss Bianca and Bernard get help from Ellie Mae, Luke, and the swamp folks on saving Penny from the greedy Madame Medusa and her incompetent sidekick Mr. Snoops.—dawsonpersi

Bernard and Bianca, of the Rescue Aid Society (a mouse organization) receive a message in a bottle from an orphaned girl who appears to have been kidnapped by Madame Medusa, a selfish woman who has no qualms about using children for her own purposes. The two mice go off to Devil's Bayou to attempt to rescue the little girl.—Tim Pickett <quetzal@yoyo.cc.monash.edu.au>

A bottle containing a plea for help arrives at the Rescue Aid Society, an organization of mice from all over the world whose mission is to help those in need. Bernard and Miss Bianca are chosen for the task and after gathering the needed clues and information, they fly on the back of albatross Orville to the gloomy and uncharted Devil's Bayou. There, together with Ellie Mae and other swamp folk, they must work together to save a little orphan girl from the evil Madame Medusa.—Frederick Irizarry

In an abandoned riverboat in Devil's Bayou, Louisiana, a 6-year-old orphan named (Michelle Stac) Penny drops a message in a bottle, containing a plea for help, into the river. After a perilous journey of crossing the ocean and encountering several obstacles, the bottle washes up in New York City.

The bottle is then brought before the International Rescue Aid Society, an organization of mice that gathers inside a luxury suitcase in the basement of the United Nations building. The mice also represent various corners of the globe and travel in the respective luggage of the UN delegates from their country. Inside the bottle is a note that is recovered by a janitorial mouse named Mr Bernard. Once the note is retrieved, the Chairman and the Hungarian representative named Miss Bianca reads the brief message. The Rescue Aid Society had never turned down a request for help. The note itself was addressed to the Morningside Orphanage.

The Hungarian representative, Miss Bianca (Eva Gabor), volunteers to accept the case as she cannot stand the notion of a little girl needing help. Bernard says that the assignment is dangerous, and Bianca should not go alone, so the Chairman allows her to pick a co-agent.

She chooses Bernard (Bob Newhart), a stammering janitor, as her co-agent. The two visit Morningside Orphanage, where Penny lived, and meet an old cat named Rufus (John McIntire). In a closet, they find a box with Penny's name on it, along with her belongings inside of it. Rufus explains that before she disappeared, Penny eagerly wished to be adopted and find a loving home. She was depressed that families did not find her pretty enough to be adopted and passed her over for other kids at the orphanage. The next time Rufus checked on her, she was nowhere to be found. However, with little information to go on, the Police have stopped looking for her and speculated that she simply ran away.

Rufus tells them about a woman named Madame Medusa (Geraldine Page) who once tried to lure Penny into her car, prompting the mice to investigate her pawn shop for clues.

Medusa is a greedy, redheaded, wicked pawn-shop owner. They come across a writing book with Penny's name in it. However, they hide quickly when Medusa appears to answer a phone call.

At the pawn shop, Bianca and Bernard discover that Medusa and her partner, Mr. Snoops (Joe Flynn), are searching for the world's largest diamond, the Devil's Eye. Medusa berates a person on the other end of the phone named Snoops, for not having found a diamond after three months, and finding out Penny has been sending messages in bottles. The angry woman tells Snoops she is heading down to the Devil's Bayou immediately, and Bernard and Bianca tag along in her suitcase. However, Medusa's erratic driving causes the luggage to spill out on the sidewalk, leaving them unable to follow her directly.

Bianca and Bernard reach the top of a skyscraper, which is a helipad for taking customers to the airport for their flights. With the help of an albatross named Orville (Jim Jordan) (who runs Albatross Air Service from the top of the skyscraper), the mice follow Medusa to the bayou. Bernard wanted to play it safe and take the train, but Bianca knew that it would take too much time, and Orville insisted that he was fit as a fiddle. Bianca and Bernard strap themselves inside a sardine can that is attached to Orville's back with a belt, and he takes off. As they reach the bayou, Orville finds himself dodging fireworks being set off by Medusa's partner, Mr Snoops, in his attempt to light up the bayou to help Medusa and her pet alligators (Nero and Brutus) find Penny, who has run away again. Medusa also goes looking for Penny in a jet boat, with very powerful flashlights.

As Orville and the two mice come down into the swamp, they encounter a couple of muskrats named Luke (Pat Buttram) and Ellie Mae (Jeanette Nolan). Luke is in the business of brewing his own moonshine. While Orville is grounded due to his tail feathers having caught fire, Ellie Mae supplies the mice with a dragonfly named Evinrude (James MacDonald), who helps power them through the swamp on a leaf. They eventually find that Medusa's alligators have caught Penny and returned her to the riverboat. Snoops fires another flare to signal to Medusa that Penny has been found and to indicate to her to return to the riverboat.

In a nearby underground cavern, there is word that a large diamond known as The Devil's Eye resides. However, the hole that leads to it is very small, and Penny was kidnapped because she could fit and retrieve the diamond. Snoops says that Penny has already retrieved a lot of other gems from the cavern, which are very valuable, but the Devil's Eye has eluded her. Medusa blames Snoops of being easy on Penny and for not leaving her in the cavern for long enough to find the diamond. Snoops says that the water was rising, and the tide was coming in and so it wasn't possible for Penny remain down in the cavern for too long. Medusa plans to put Penny in the cavern at the next low tide and to keep her there till she finds the diamond.

Bianca and Bernard learn of Medusa's plan for Penny. Nero and Brutus smell Ms Bianca's perfume and attempt to catch the two mice. When Medusa sees the two mice, she panics and begins to blast them with a shotgun. The chaos allows Bianca and Brutus to escape into the swamp and they are rescued by Evinrude.

Bernard is close to giving up, but Bianca reminds him that Penny is counting on them for her rescue. Bernard and Bianca find Penny and devise a plan of escape. They send Evinrude to alert the local animals, who loathe Medusa, but Evinrude is delayed when he is forced to take shelter from a cloud of bats. The following morning, Medusa and Snoops send Penny down into the cave to find the gem. Unknown to Medusa, Bianca and Bernard are hiding in Penny's dress pocket. The three soon find the Devil's Eye within a pirate skull. As Penny pries the mouth open with a sword, the mice push the gem through it, but soon the oceanic tide rises and floods the cave. The three barely manage to escape with the diamond.

Medusa betrays Snoops and hides the diamond in Penny's teddy bear, while holding Penny and Snoops at gunpoint. When she trips over a cable set as a trap by Bernard and Bianca, Medusa loses the bear and the diamond to Penny, who runs away with them. The local animals arrive at the riverboat and aid Bernard and Bianca in trapping Brutus and Nero, then set off Mr. Snoops' fireworks to create more chaos.

Meanwhile, Penny and the mice commandeer Medusa's swamp-mobile, a makeshift air-boat. Medusa unsuccessfully pursues them, using Brutus and Nero as water-skis. As the riverboat sinks from the fireworks' damage, Medusa crashes and is left clinging to the boat's smoke stacks. Mr. Snoops escapes on a raft and laughs at her, while the irritated Brutus and Nero turn on her and circle below.

Back in New York City, the Rescue Aid Society watch a news report of how Penny found the Devil's Eye, which has been given to the Smithsonian Institution while it is implied that Medusa and Mr. Snoops have been arrested. It also mentions she has been adopted. The meeting is interrupted when Evinrude arrives with a call for help, sending Bernard and Bianca on a new adventure.