“My mother always tells me to smile and put on a happy face,” the sadistic Batman villain says over the new footage.
Zazie Beetz, Brian Tyree Henry and Brett Cullen all appear in the trailer, as does Robert De Niro, who plays a talk show host.
Todd Phillips (The Hangover trilogy, War Dogs) has directed Joker, with Phillips, Bradley Cooper and Emma Tillinger Koskoff acting as producers.
Phoenix’s character – who remains unconnected from Jared Leto’s version of the character in Suicide Squad – starts as a struggling comedian, much like Rupert Pupkin (played by De Niro) in Martin Scorsese film The King of Comedy.