Dylan O’Brien is in negotiations to lead Peter Farrelly’s Vietnam War movie, joining Green Book actor Viggo Mortensen, who has a supporting role in the film. Based on the book by Joanna Molloy and John “Chickie” Donohue, The Greatest Beer Run Ever: A True Story of Friendship Stronger Than War, the movie tells true story of Donohue, who left New York in 1967 for Vietnam to track down and share a few beers with his childhood friends, who were serving in the Army.