The Newton family from the first two Beethoven movies is on vacation in Europe, but they do plan to attend a Newton family reunion, and to make sure one of their family members definitely makes it ...
There's more to work than life.
The family is pleasantly surprised and puzzled when Beethoven suddenly becomes obedient. Turns out it's a prince and the pauper scenario, with the real Beethoven now living with a pompous rich family.