Jessica Chastain (The Debt) is set to star in the Princess Diana biopic Caught in Flight for director Oliver Hirschbiegel (Downfall).  According to Thompson on Hollywood, the movie will revolve around Diana’s real-life secret affair with heart surgeon, Dr. Hasnat Kahn, “who was said to be the love of her life.”  Their two-year affair began in 1995, and Kahn maintained his silence until he spoke on record to The Telegraph in 2008.  TOH adds that the movie is described as a “love story between a princess locked in a tower and an ordinary man.”  Some would say that Di was just a girl, standing in front of a boy, asking him to love her.

Hit the jump for more on the project.  Pre-production is set to begin in March 2012.  Chastain will next be seen in Ralph Fiennes Coriolanus, and she’ll star opposite Tom Cruise in the sci-fi blockbuster Horizons.