This odd coupling invites two icons to break character. Nelson revisits American classics with serious jazzmen; check his beat-tugging guitar on "My Bucket's Got a Hole in It." And Marsalis, not the mellowest genius, chills out, adding a one-note trumpet solo on "That's All" that's funny and awesome. Even when things don't click, the improvisatory spirit shines.

“1999”

“I don’t consider myself a great poet,” Prince told Rolling Stone. “I just know I’m here to say what’s on my mind.” In the case of the apocalyptic party anthem “1999,” he was worried about then-president Ronald Reagan’s foreign policies. The song’s melody is based on a riff borrowed from the Mamas and Papas’ “Monday, Monday,” and Prince originally envisioned the first verse with three-part harmony but later split the vocals between himself and members of the Revolution. Because Warner Bros., with whom Prince was locked in a contractual battle, owned the original’s masters, Prince rerecorded the song and appropriately released that version in 1999.