All-Star Comics #19

Hawkman has disappeared, and as the members make ready for a meeting that will not take place, hawks begin arriving with fragments of sheet music, each one with a single note on it. The members gather at a deserted country house to try and figure out what the notes mean. Wonder Woman sits at a piano in the house and plays one of the notes. Immediately, a small panel opens in the piano and out falls a hammer with a note attached, giving a name and address, along with a cryptic notation. Each member takes one of the notes to follow them up to see if they lead to the whereabouts of Hawkman.