Alicia Keys is producing a Broadway play. Why not? She’s conquered pop music, that’s for sure. The play, “Stick Fly,” will star Ruben Santiago Hudson, Mekhi Phifer (“ER”), Tracie Thoms, and Dule Hill (from the show “Psych”). Lydia Diamond wrote the play, which will be directed by Kenny Leon. Santiago-Hudson is one of the best actors of his generation, so this is particularly exciting. That Alicia has gotten involved in this also shows how interesting her career has become. The lead producers are Nelle Nugent, Alicia Keys, Samuel Nappi, Reuben Cannon, Sharon A. Carr/Patricia Klausner, Huntington Theatre Company, Dan Frishwasser, Charles Salameno in association with Joseph Sirola & Eric Falkenstein. “Stick Fly” opens December 8th at the intimate Cort Theater on West 48th St.