Madonna has posted the sheet music for what appears to be a new song.  

According to Billboard, a scan of the page titled "Messiah" is up on Instagram.  But it lacks composer credit, so we're unsure of who wrote it.  There's also a caption "Coming soon...#promise #keep #sorceress #deep."

Adding to the mystery is a brief video on Madonna's page showing a classical orchestra performing a serious piece in a recording studio.

Several months back, Madonna said she was working on the follow-up to her 2012 MDNA album.  More recently, she mentioned on Instagram that she was going to work in the studio with the European dance music star Avicii.  We'll see what happens.

Here's Madonna's 1984 classic "Like A Virgin" from iHeartRadio.  This was all over MTV in '84 and '85.