The film is an adaptation of British TV host and producerRichard Osmans novel of the same name.
Mirren will play ex-spy Elizabeth, Kingsley will play ex-psychiatrist Ibrahim and Brosnan will play former union activist Ron.
Negotiations for an actress to play the fourth member of the group, Joyce, are ongoing.

Pierce Brosnan, Helen Mirren, Ben Kingsley and Chris ColumbusGilbert Flores/Variety via Getty Images; Tristar Media/WireImage; Paul Archuleta/Getty Images; Steve Jennings/Getty Images
He sold the rights toThe Thursday Murder Clubto Spielberg in 2020, and work has been ongoing since then.
Osman is best known as a British TV presenter on BBC game showPointlessandRichard Osmans House of Games.
He has numerous appearances on UK comedy shows such as8 Out of Ten Cats Does Countdown.

He officially left the company in 2020, when it was known as Endemol Shine UK.
Jeff Sneider first had news of the casting.