Robert Downey Jr. is slated to spend approximately three months filming Avengers: Doomsday, while the film’s main heroes will each shoot their scenes over the course of about one month starting in March. Characters with smaller roles are expected to film for just 1-2 weeks.
The entire production is anticipated to take around five months to complete. Robert Downey Jr. Set for Three-Month Shoot on Avengers: Doomsday