Batman: The Dark Knight Returns #1 is said by many to have ushered in the age of modern comic books.  Whether you agree or not, it is still a GREAT read and a huge Copper Age key.  It's Frank Miller at the pinnacle of his career.  First appearance of Carrie Kelly, who later becomes Robin.  This book is graded 9.4 NM with white pages by CGC.  This is the FIRST PRINTING.  No Batman collection is complete without this series.