Superman #19

Superman must battle a new villain who has invented a machine that can materialize two-dimensional figures out of the comics to rob for him. This issue features ‘imaginary’ Superman stories – stories that either do not actually happen in Superman continuity, or somehow break 4th wall. Case of the Funny Paper Crimes – Clark and Lois love reading the adventures of their favorite heroes in the Daily Planet’s funny pages. But suddenly reports start pouring into the Planet’s office of crimes being committed all over Metropolis by giant characters right out of the daily funnies! Is this some kind of hoax?