Linus sneaks into the chateau where he confronts the baron's neice Violette in the attic. Here he learns the truth of how she knows of Charlie Brown: her grandmother and his grandfather were lovers in the past.
Just then, the baron returns home early. In their panic, Linus and Violette accidentally knock over a candle, igniting a fire. Charlie Brown runs to the house where Peppermint Patty and Marcie are staying with Pierre to call for help. With help from the arriving fire department, Snoopy puts out the fire. With Linus' blanket, Linus and Violet escape safely.
Grateful for the rescue of his niece and his house, the baron allows the boys and girls to stay in the chateau for the rest of their visit. When it is time to go home, Peppermint Patty decides to break off her "relationship" with Pierre as a long distance relationship would never work out, Marcie and Pierre kiss. They bid farewell to their French friends and drive off.
Before the credits (which also feature pictures of everyone who made the movie), their car is rear-ended again with Marcie once more shouting epiphets to the other drivers. Snoopy drives off laughing.