'Man of Steel' Star Michael Shannon -- The King Has Entered the Building

"Man of Steel" star Michael Shannon will soon strap on Elvis' blue suede shoes for a feature film ... and the actor chilled suspicious minds during a concert in Chicago with a pretty awesome live performance.

Shannon is set to play Elvis in an upcoming flick about the day Richard Nixon met the King -- with Kevin Spacey reportedly playing the Prez. -- and we got footage of the actor working on his Presley.

During his set with a Lou Reed cover band, Michael talked about the upcoming role -- and then gave the audience a preview of his Elvis pipes with a rendition of "Blue Suede Shoes."

Would Elvis approve? Sound off in the comments.