John Williams‘ music for “Disclosure Day” marks his 30th score for director Steven Spielberg, dating back more than half a century to their first film together, “The Sugarland Express” in 1974.

It could be Williams’ final score for the movies. No one has formally stated that, and in fact Spielberg says he’s already spoken to Williams about doing their 31st together.

But Williams is now 94, and hinted three years ago that his score for Spielberg’s “The Fabelmans” would likely be his swansong. The director talked him into doing “Disclosure Day” even after Williams suggested four other composers as possible successors.

Williams is no longer doing press interviews (“preferring to marshal his energies to focus on writing obligations,” says a spokesman) and Spielberg was not available for this story.

Multiple sources say Spielberg wanted a Williams score for “Disclosure Day” so badly that he made it as easy as possible for the composer, scheduling seven recording sessions over a six-month period to give him the necessary time to conceive and record all of the music.