Robert Downey Jr.
Actor Robert Downey Jr. arrives at the European premiere of "Captain America, Civil War" at a shopping centre in east London, Britain April 26, 2016. Reuters/Toby Melville

While the future of “True Detective” Season 3 is still in limbo, its writer Nic Pizzolatto is busy gearing up for a new HBO television series.

Reports say that Pizzolatto is currently working with “Iron Man” star Robert Downey Jr for an upcoming crime drama, which is an adaptation of the classic US detective show “Perry Mason.” The project has been in the works since May this year, according to Variety.

“Perry Mason” was a successful, long-running American legal drama series that ran on CBS from 1957 to 1966. The title character, played by Raymond Burr, was a criminal defense lawyer, based on the detective fiction penned by Erle Stanley Gardner. In 1973, there was an attempt to revive the series, starring Monte Markham and Sharon Acker, but it was received poorly and the show wrapped up after only half a season. NBC, on the other hand, aired a series of TV movies between 1985 and 1995. Burr reprised his role and worked in 26 out of 30 movies.

According to Variety, Downey Jr has been interested to pursue to “Perry Mason” project and originally wanted a film adaptation in 2011 with Warner Bros. However, plans didn’t pan out and the 51-year-old icon focused his energies on another legal drama film, “The Judge” which hit theatres in 2014.

“Perry Mason” marks Downey Jr’s big television comeback. In the early 2000s, he starred in “Ally McBeal” as Larry Paul, who served Ally’s (Calista Flockhart) love interest in the fourth season of the comedy-drama series. Since Downey Jr left “Ally McBeal,” he has built himself into one of the biggest movie stars in the industry, widely credited for his role as an iconic Marvel hero. In 2015, he was named the world’s highest-paid actor with a whopping $80-million (AU$109 million) paycheck. The “Avengers” star earned US$75 million (AU$102 million) in 2013 and again in 2014.

Meanwhile, “Perry Mason” also ensures Pizzolatto a high-profile project while waiting for developments on “True Detective.” Last month, HBO assured fans that the series is “not dead” yet, although there hasn’t been any update for over a year.