Three years later in 1983, the film was followed by a TV special, "What Have We Learned, Charlie Brown?"
The film begins in France, at a bar in a village where lively music is playing. A man departs the bar, getting into his car. As he drives home, it starts to rain and he passes some greenhouses. He arrives at a chateau, where a little girl begins writing a letter and is seen with a US Army stachel stenciled with the name "S. BROWN".
In the United States, Linus is introducing two French students, Babette and Jacques, who will be spending spending two weeks at Charlie Brown's school, while Charlie Brown, himself, Peppermint Patty, and Marcie go to France. At the airport, the children, Snoopy and Woodstock are seen off by their friends. Lucy, who was not selected for the program, tells Charlie Brown not to come back.
During the flight, Charlie Brown produces a letter he received that was written in French. Marcie, who has been studying French, translates it and says it is an invitation from a young girl, VioletteHonfleur to stay at the Chateau du Mal Voisin (The Castle of the Bad Neighbor). Peppermint Patty asks who this Violette could be, Charlie Brown has no idea.
The group first arrive in London and go on a sightseeing tour downtown, while Snoopy and Woodstock play some tennis at Wimbledon. When Snoopy finds himself losing, he lashes out and gets thrown off the court. Snoopy and Woodstock head to the Victoria Railway Station and rejoin the rest of the group. The group looks at the English countryside while traveling to Dover, then finally arrive to briefly admire the White Cliffs of Dover before boarding a hovercraft that will cross the English Channel. They eventually arrive in France. Marcie uses her French skills to get a rental car for the group (and resulting in some humorous scenes where she curses out other drivers during a traffic jam), and Charlie Brown buys some French bread. They drive to a farmhouse where Peppermint Patty and Marcie will be staying with Pierre. Pierre is a gracious host who appreciates Marcie making an effort to learn his native tongue, but Peppermint Patty thinks he must have an obvious crush on her. Pierre then gets worried that Linus and Charlie Brown went to the Chateau Malvoisin, as it must be some mistake as no one has ever stayed at the Chateau. When Marcy asks about it, Pierre says the Chateau is owned by the Baron, a vile reclusive man who hates everybody, especially foreigners. Pierre makes some phone calls in an attempt to find Charlie Brown, but no one has seen him and Pierre says he is afraid he cannot help Linus or Charlie Brown until they meet up at school.
When Charlie Brown and Linus arrive at the Chateau, a thunderstorm forces them to spend the night in an empty stable. Later that night, Snoopy (in his "World War I Flying Ace" persona) and Woodstock head down to local pub to drink a few pints of root beer.
The next morning, Charlie Brown and Linus find that breakfast and warm blankets have been set up for them by some unknown benefactor. Meanwhile at Pierre's farm, Marcie and Peppermint Patty help with Pierre's chores, while Peppermint Patty, oblivious to Pierre's attitude, tries to tell Marcie that he likes her. Peppermint Patty then experiences culture shock as Pierre's family eats soup and sausage for breakfast and that she and Marcie will have to wear a school uniform while back in the States she wore her own clothes to school. Marcie adopts a "When in Rome" attitude and simply tells Peppermint Patty than when one is a guest of a foreign land, one must respect their ways.
When the gang meets each other at school, Charlie Brown produces the letter from Violette. Pierre says that Violette is a niece of the baron who owns the chateau; since the Baron is antisocial, it clearly must have been Violette who invited them to the Chateau. In a reversal of the first scene where Babette and Jacques were introduced to school back in the States, the teacher at the French school introduces Marcie, Peppermint Patty, Linus and Charlie Brown to her class. The teacher is a nice woman who also says that while the four American kids are in class she will split the instruction between French and English to help teach her own class some English words and to accomodate the exchange students. The class sits at tables; and Charlie Brown is made to sit next to Peppermint Patty, resulting in a brief humorous scene, consisting of Charlie Brown angry at Peppermint Patty for criticizing him.
That night, the baron leaves the chateau to go to the pub and instructs Violette not to let Charlie Brown and Linus in, despite Violette protests that they must be hospitable as their family was many years ago, but the Baron is adamant they are not to come in. Meanwhile, Charlie Brown and Linus take turns to stand and watch to identify the mysterious benefactor. During Charlie Brown's watch, Linus wakes up to see Charlie Brown has fallen asleep. Linus then goes into the chateau to get to the bottom of this. Eventually, he finds Violette, who says her invitation was a mistake. Violette explains that her grandmother had told her the story of a wartime affair that she had with Silas Brown, Charlie Brown's grandfather, who was an infantryman stationed in France during World War I, and stayed at the chateau. When Silas received his marching orders, he promised to write letters which eventually stopped coming. Violette's grandmother moved on, though she never forgot him. Linus remarks that Silas looks like a full-grown version of Charlie Brown.
Meanwhile at the pub, Snoopy and Woodstock are playing foosball and overhear the baron confide to the bartender that he knows about Charlie Brown and Linus and has tolerated them long enough, planning to do terrible things to them should they fail to leave by morning. The baron returns home to Violette's surprise, and in her rush to get Linus out of the room, Violette accidentally knocks over a candle which causes a fire throughout the chateau. Linus takes Violette towards a pair of casement windows, throws them open and shouts to Charlie Brown for help. Charlie Brown wakes up and runs to the pub to call Snoopy and Woodstock. Snoopy and Woodstock rush off to the Chateau and Charlie Brown continues running to the farmhouse to call Peppermint Patty, Marcie and Pierre. Pierre calls the fire department while Peppermint Patty and Marcie follow Charlie Brown to the flaming chateau.
When Snoopy and Woodstock arrive at the chateau, it is engulfed in flames. Snoopy immediately heads to a shed and brings out an old fashioned fire hose, while Linus throws his blanket down to Charlie Brown, Peppermint Patty, Marcie and Pierre, which they use to catch Violette when she jumps out the window. Snoopy arrives with a barrel of water under Linus who also jumps to safety, and later barks out instructions to work the hose, but the intense water pressure spins him around, splashing Charlie Brown. Woodstock pops out from the hose with a violin and begins playing along to the dramatic scene. While Snoopy is working with the hose, a fire truck with four shadowed firefighters arrives and the fire is finally extinguished.
The baron, who is thankful that the group saved Violette and the chateau, promises he will never be inhospitable again, and now hosts Linus and Charlie Brown inside the chateau like a proper host. Charlie Brown learns the whole truth behind the mysterious letter he received. Many years ago, an friend of Violette's family was touring the United States and needed his hair cut at one point, and the barber was Charlie Brown's father. This news about the location of the Brown family inspired Violette to write a letter inviting him to stay at the Chateau. As the group prepares to leave the chateau to return to America, Violette gives Silas' satchel to Charlie Brown. The film ends when the group say their goodbyes and get into their beat-up rental car.
The credits show pictures of the film's crew as a collage of designs show the flags of the United States, United Kingdom, and France, the three nations in which the film is set.
- Arrin Skelley as Charlie Brown
- Daniel Anderson as Linus van Pelt
- Patricia Patts as Peppermint Patty
- Casey Carlson as Marcie
- Annalisa Bortolin as Sally Brown
- Laura Planting as Lucy van Pelt
- Bill Melendez as Snoopy & Woodstock (vocal effects)
- Pascale De Barolet as Pierre
- Roseline Rubens as Violet Honfleur
- Scott Beach as Waiter, Baron, Driver, Tennis Announcer, English Voice & American Male
- Tim Stack as Snoopy (speaking voice)
- Eric Meyers as Woodstock (speaking voice)
"Bon Voyage, Charlie Brown" was the fourth & last theatrical Peanuts film overseen by creator Charles M. Schultz (who died in 2000).
It's also the only Peanuts feature film to featured adults on-screen with speaking parts instead of the usual "wa-wa-wa" sound that is usually heard in the Peanuts cartoons.
"Bon Voyage, Charlie Brown" grossed $2,013,193 domestically at the box office.