48-year-old Damon was seen leaving his BFF Affleck's house on Monday morning in Los Angeles, and was seen holding a book and a script. The script appeared to have pens stuck in it, as though notes were being made on the text.
We did some digging, and the book appears to be, "The Last Duel: A True Story of Trial by Combat in Medieval France'' by Eric Jager.
"The Last Duel" details the events surrounding the last officially recognized judicial duel fought in France. It tells the story of the December 29, 1386 trial by combat between Norman knight Jean de Carrouges and the squire Jacques Le Gris.
The film is currently listed in development on IMDB, and although no cast has been announced, it is reportedly going to be directed by Francis Lewis, who is known for "The Hunger Games: Catching Fire," "Constantine" and "I Am Legend," among others.
From the looks of it in this pic, Damon was over at Affleck's house going over the script.
Ben and Matt are longtime friends from Boston and previously scored Oscars for their 1997 hit film, "Good Will Hunting."
Their bromance grew from that point with the two working on numerous projects throughout the years including their "Project Greenlight" TV series, which gave up and coming filmmakers the chance to direct their first feature film.
Both stars also appear in the upcoming Kevin Smith movie, "Jay and Silent Bob Reboot."
It's unclear if the stars are eyeing themselves for roles in "The Last Duel," or are perhaps interested in producing a project.