Irons, who has also been seen on Broadway in Impressionism, will play Cambridge professor G.H. Hardy, the English mathematician who brought Ramanujan (Patel) to Cambridge University.
Matthew Brown will direct from a screenplay he wrote based on the biography "The Man Who Knew Infinity: A Life of the Genius Ramanujan" by Robert Kanigel.
"The Man Who Knew Infinity" is scheduled to shoot in the U.K. and India in 2014.
Edward R. Pressman and Prashita Chaudhary of Cinemorphic Entertainment Company are producers along with Jim Young and Sofia Sondervan. Jon Katz, Tristine Skyler, Joe Thomas, Pamela Godfrey, Mark Montgomery and Min-Li Tan are executive producers, and Tayyab Madni will serve as an associate producer.