The new promo photos and videos released by Fox for the season 2 premiere of "Gotham" provided fans a glimpse of what are in store for the series — the batcave and the growing roster of villains that would bring chaos to the city.

TV Insider reports that the image showing "a hidden lair" underneath the Wayne Manor is technically the Batcave that Bruce will be using as his hideout/center of operation in the future. The photo, which was teased in last season's finale, depicts young Bruce (David Mazouz) and his faithful manservant Alfred (Sean Pertwee) exploring the grotto.

Mazouz has previously revealed in an interview that the cave was a game-changer for his character's life. Its discovery would purportedly alter how he sees the people closest to his heart, namely his deceased parents and Alfred. The cavern would also prompt him to view the ugly side of Gotham, with its crime and corruption. The young actor also reiterated that at this point in the story, viewers could not call it the Batcave.

"It's definitely not the Batcave. What is down there are clues to Thomas Wayne's secret life and what he was trying to do before being killed," he said.

Meanwhile, the new teaser released by the network shows the other bad guys who would give the Gotham police a run for its money. Theo Galavan (James Frain) could be heard speaking throughout the video, saying that the city would "tremble" before him, after he has caused mass panic.

Another villain, Tabitha Galavan aka Tigris (Jessica Lucas) was also revealed, with blood splatters all over her face. Jerome Valeska (Cameron Monaghan), with his maniacal laugh, was frequently shown in the promo. While it looked like he could really be Batman's crazy foe, The Joker, executive producer Bruno Heller hinted that he may not be the said character.

In an interview with E! Online, Heller was very vague in answering the straight question whether or not Jerome is actually the villain everyone is expecting him to be. What was clear, however, is that he would first encounter protagonist Jim (Ben McKenzie) in a circus, where Jerome appeared to be working.

The executive producer said, "This is not a red herring. It's the beginning of the story of how the Joker came to be, how the Joker was created, where he came from, who he is. Now, that doesn't necessarily mean that Cameron Monaghan is the Joker. He might be."

"Gotham" season 2 will premiere on Monday, Sept. 21 on Fox.