'Avengers: Infinity War' Directors, Downey Ask for Secrecy

FILE - Robert Downey Jr. is interviewed at the premiere for the film "The Avengers Age of Ultron" in London, April, 21, 2015.

Actor Robert Downey Jr. is joining the directors of Avengers: Infinity War in calling for fans to maintain secrecy.

The star tweeted "no spoilers please." He signed it with the #ThanosDemandsYourSilence. Thanos is the fictional Marvel Comics villain who will be portrayed by Josh Brolin in the movie. Downey plays Iron Man.

Directors Joe and Anthony Russo went on Twitter to tell fans they would be screening a limited amount of footage prior to the film's release on April 27. They say "only a handful of people know the film's true plot."

They asked fans to maintain the same level of secrecy so that they don't spoil it for others.