According to The Hollywood Reporter, Mel Gibson is set to star in Voltage Pictures’ The Professor and the Madman, a film depicting the true story of the creation of the Oxford English Dictionary. Sean Penn is in negotiations to star opposite Gibson.

Gibson had acquired the film rights to the Simon Winchester book 15 years ago. Originally developing the project as a directing vehicle, he will instead be in front of the cameras, while screenwriter Farhad Safinia (Apocalypto) will helm. Todd Komarnicki and John Boorman wrote earlier drafts of Safinia’s screenplay.

Gibson will play Professor James Murray who took on the extremely ambitious goal of creating the Oxford English Dictionary in 1857. Penn will play Dr. W.C. Minor, who submitted more than 10,000 entries but also was institutionalized in an asylum for the criminally insane.

Gibson, who possesses two Academy Awards for directing and producing Braveheart, directed the upcoming Hacksaw Ridge, to be released by Lionsgate on November 4th. In front of the cameras, he has been seen recently in The Expendables 3 and The Beaver. He will be in the upcoming Blood Father.

Penn, with two Oscars to his name for best leading actor in Mystic River and Milk, directed Charlize Theron and Javier Bardem in The Last Face. He will both helm and star in the drama Flag Day, which is scheduled to be released in 2018.

Shooting is scheduled to start in September in Europe.