Last weeks Human for a Day saw it finally revealed that Hank Henshaw wasnt really Hank Henshaw: instead, he was actually Jonn Jonnz, aka the Martian Manhunter. In the comic book realm, Martian Manhunter is a founding member of the Justice League. What we got here, though, was a reference seemingly to Jonn being a friend of Supermans in the world that the show exists in. Whilst Jonnz/Henshaw makes reference to Alex about his capability to read peoples minds, he quips about how Superman finds it hilarious that Kryptonians are impervious to his mind-reading capabilities. Clearly the Martian Manhunter and Kal-El have had previous and are good pals, with this maybe being something that the show could refer to at times again in the future.