It's traditional for a movie to have a soundtrack. It's less traditional for a movie to borrow most of its soundtrack from a dude who's been dead for 238 years.

The bulk of Kramer vs. Kramer's score is "Mandolin Concerto in C Major" by Vivaldi—Antonio Vivaldi, that is, the 18th-century Italian classical composer. ("Tony" to his friends; we're just assuming.) Being in C major, not minor, the clips of the concerto used in the film—primarily from the concerto's first movement—are bright and airy. The music moves quickly, just like Ted and Joanna's hustling and bustling New York. If you're assuming that the fact that it's classical music automatically makes the upper middle-class family drama on screen seem more sophisticated and dramatic, well, you're right.

What's extraordinary about the film's score isn't that it's a borrowed Baroque mandolin jam, though. It's that it's physically rooted in the film itself very early on.

By that we mean, in the film's first scene, as Ted and Jim leave work, they walk down the street and pass a pair of street musicians playing Vivaldi's concerto which seamlessly blends into the score. While the film doesn't go so far as to suggest that these two buskers are following Ted, Joanna, and Billy around for the duration and playing its classical score, live, just out of frame, it's still a unique approach to integrating the greatest hits of 1725 into the movie's soundtrack.

The iconic French film director Francois Truffaut had been Columbia's first choice to direct Kramer, but he was busy with other projects and declined. Director Benton said he used the Vivaldi piece as a nod to Truffaut: it was part of the score for his famous 1970 film The Wild Child (L'enfant Sauvage). You might remember Truffaut, who was one of the founders of the avant-garde French New Wave cinema movement, from his turn as the French scientist in Close Encounters of the Third Kind.

Classy move, Mr. Benton.