During New York Comic-Con last month, Gotham executive producer Danny Cannon was asked if the villainous Harley Quinn will make an appearance, although he didn't specifically say whether or not she will be popping in during the first season. During an interview with Entertainment Weekly, series creator Bruno Heller clarified that there are plans for Harley Quinn down the line, but not in the first season.
"One of the things about the size and scope and ambitious of this production is that - it's not that there's lots of chefs in the kitchen, but there's a lot of people with opinions and views and inside knowledge. That aspect of the show - which characters to use and when - is a source of constant discussion. And that may well have been an issue that came up and was dropped. We haven't got Harley Quinn in it. Riddler's girlfriend is coming up. And Harley Quinn is definitely planned for later on, but so far no. You can't just keep pumping these characters into the show in a comic book sort of way, because you get the Super Friends effect - which isn't a bad effect, but then you have spaceships and need to go underwater and get wacky villains and the rest of it. You have to work as a character piece first. First it has to be real."
Gotham star Ben McKenzie teased in an interview last week that fans may get to see the parents of Dick Grayson, the future Robin, at some point in Season 1. Bruno Heller confirmed that fans will get to meet the Grayson family, but before Dick is even born.
"We're going to do a prenatal origin story for Robin down the line. There are no MRIs involved. There's an episode coming up where we learn how Robin's parents got together."
He also confirmed that fans will get to see the future Scarecrow, although it isn't immediately clear when he will debut.
"This is not a kid being a loony Scarecrow; this is a couple episodes about how that character has evolved - everyone's character is formed in their childhood to some degree or another. His father is involved, as is part of the [character's] mythology."
Bruno Heller added that Ivy Pepper, a.k.a. the young Poison Ivy (Clare Foley), will return, and he confirmed a report from July that they plan on teasing the audience by introducing several characters who may or may not become The Joker.