The director of Joker has reiterated that no sequel is currently in the works, but Todd Phillips has spoken to what he thinks a Joker sequel would need to do to be worth making.
Phillips told The Los Angeles Times that a sequel would need that same dramatic heft that has been at the crux of what he believes is why audiences have been so supportive of the film.
“…It couldn’t just be this wild and crazy movie about the ‘Clown Prince of Crime,’” Phillips said. “It would have to have some thematic resonance in a similar way that
does. Because I think that’s ultimately why the movie connected, it’s what’s going on underneath. So many movies are about the spark, and this is about the powder. If you could capture that again in a real way, that would be interesting.”
Source: IGN.com Joker Director Will Only Make a Sequel If It Has 'Thematic Resonance'