Joaquin Phoenix is back as Joker to unleash chaos in the first teaser trailer of "Joker: Folie a Deux", which also introduces viewers to the love of his life in Harley Quinn, played by Lady Gaga.

Hollywood studio Warner Bros unveiled the first look of the follow-up to the multiple Oscar-winning antihero saga "Joker", which was released in 2019.

Phoenix won the Academy Award for best actor for his turn as a failed, unhinged stand-up comedian who descends into chaos, taking the whole Gotham City along with him.

Often teased as a psychological thriller with elements of a musical, the sequel presents a twisted tale of love between Phoenix's Arthur Fleck aka Joker and Quinn, played by Gaga.

The trailer opens with Fleck still locked up in Arkham, the asylum in Gotham City where most of DC comics villains end up. He finds a glimmer of hope when he meets Quinn. The two are shown running through the streets, watching movies together and dancing against a moonlit sky. In one of the sequences, Fleck is dressed in the Joker avatar and performing at a nightclub.

Just like the first part, the trailer does not make it clear what is real and how much of it might just be happening in Fleck's head.

Todd Phillips returns to direct. He has also co-written the script for the sequel, which will feature Zazie Beetz coming back as Sophie Dumond, a single mother and Fleck's former neighbour.

The newcomers include Brendan Gleeson, Catherine Keener and Steve Coogan.

Warner Bros will release "Joker: Folie a Deux" in Indian theatres on October 4 in English, Hindi, Tamil and Telugu languages.