Robert Downey, Jr.: "Talk to Me, Twitter"

Marvel's The Avengers

and Iron Man star Robert Downey, Jr. joined Twitter today, generating more than 55,000 followers in the 20 minutes since his first tweet. Downey, in production on Avengers: Age of Ultron at present, took even longer to join the social media network than did the film's director, Joss Whedon, who came on board in May 2013, during the ramp-up to his passion project, the black-and-white, micro-budget Much Ado About Nothing he directed with a number of actors he regularly works with including Marvel's Agents of S.H.I.E.L.D.'s Clark Gregg and Amy Acker. You can check out his first tweet and follow him below -- and maybe soon we'll find out just what he joined to promote.

Talk to me, Twitter. pic.twitter.com/7skFm6Ffhn — Robert Downey Jr (@RobertDowneyJr) April 11, 2014