'Gotham' has without a doubt only gotten better with time, with the city's origin story delving into the stories of the heroes, villains and everything in-between. Making its return for a fourth season tomorrow night (September 21) on FOX in the US, information about what fans can expect from new episodes is beginning to trickle out.

David Mazouz as Bruce Wayne in 'Gotham' season 3David Mazouz as Bruce Wayne in 'Gotham' season 3

We already know that Alexander Siddig will be taking on the role of Ra's al Ghul - one of Bruce Wayne's most formidable opponents if the history of Batman is anything to go by. It looks like his legacy as one of the most evil villains in DC Comics history is set to continue with this live action adaptation if actor David Mazouz's words are anything to go by.

In a chat with Rotten Tomatoes, the actor - who plays a young Bruce Wayne in 'Gotham' - explained of Bruce's future within the show: "Ra’s al Ghul is his biggest villain. He’s going to be putting him through mental torture, but also he’s going to take on The Penguin pretty early on."

Then asked how he stacks up to the other versions of Ra's we've seen, and if he'll be the most evil Ra's to-date, Mazouz replied: "Yes, absolutely. I would say this is the most evil Ra’s al Ghul. This is the Ra’s al Ghul that will do awful, awful, very, very controversial things that I’m surprised they’re letting us do on national television."

Those last few words are certainly interesting. If Mazouz is shocked about what's being done with the character because of the level of violence or something similar, then it's certainly going to make for some jaw-dropping and memorable scenes down the line.

Of course, this could all be fluff to ensure people tune in when the series makes its comeback. With its first new episode right around the corner, it won't be long before we find out exactly what's going down on the murky streets of Gotham...

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'Gotham' returns to FOX in the US for its fourth season on Thursday, September 21.