We all thought that Jerome was officially Joker with all the screen time he was getting in the Season 2 of Gotham. But since he died in Episode 3(we are all sad) the ending of Episode 3 revealed the origin for Joker in Gotham. Gotham creator Bruno Heller told us.
That story is going to come to a huge and shocking resolution which will explain the whole Joker myth and how it began and how the Joker came to be.
In Episode 3 we saw a lot of people in Gotham going crazy after the show Jerome put on in front of cameras, which will influence somebody to become the Joker we all love.