What in the Sam Hill?
What in (the) Sam Hill?
interrog. What has happened?; What? (An elaboration of what. Sam Hill is hell. Often with the force of an exclamation. See examples for variations.) What in the Sam Hill do you think you are doing?
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.