Even with the current brand-wide reset that DC's film studio is undergoing, there's been very little indication that Todd Phillps' sequel to Joker was ever considered for the chopping block. After grossing a billion dollars on a budget of $70 million, Warner Brothers was discussing a sequel to Joker before the film wrapped its opening weekend. It's not only good business to make a sequel; it's a safe bet.
However, even though Joker 2 is potentially one of the safest bets in all of Hollywood right now, Todd Phillips decided to live dangerously by constructing the film as a musical. One of the central components that made the original a massive success was the gloomy tone that permeated the movie. By choosing to make the flick a musical, Phillips is taking a considerable risk by possibly alienating the franchises' installed fan base.
In an attempt to quell fan apprehension while simultaneously stoking the embers of their excitement, Phillips just released a photo of Lady Gaga and Joaquin Phoenix as Harley Quinn and the Joker, respectively.