stephen sondheim
A musical theater composer and lyricist, known for such works as Sweeney Todd, Into the Woods, A Funny Thing Happened on the Way to the Forum, Sunday in the Park with George, among many many others. He is widely regarded as a genius, for his extremely clever lyrics and inner-rhyming trickery.
I just saw Sweeney Todd, and it was the most brilliant and creepy thing I've ever witnessed. Stephen Sondheim is a genius.