Hollywood A-lister Robert Downey Jr has signed up to play Iron Man in two sequels to the blockbuster superhero action film \"The Avengers,\" comic book giant Marvel announced Thursday. Downey Jr will reprise his role as tortured tycoon Tony Stark, who donned his metal suit to save the world as Iron Man alongside Captain America, Thor, Black Widow and the Hulk in the first \"Avengers\" movie last year. Cult director Joss Whedon will again write and helm \"The Avengers 2,\" which is slated to begin production in March 2014 and open in theaters on May 1, 2015, according to a statement on Marvel\'s website. The second installment in the franchise will feature \"favorites from the first \'Avengers\' film and new Marvel characters never before seen on the big screen,\" it said. No release date was given for \"The Avengers 3.\" The first \"Avengers\" movie and this year\'s \"Iron Man 3\" are among the top five grossing films ever, together earning more than $2.7 billion worldwide to date, Marvel said. \"The Avengers\" -- in which the superheroes help save Earth from mythical prankster Loki and an alien army -- opened in North America last May with a staggering $207.4 million in ticket sales -- the biggest US debut of all time. With an estimated budget of $220 million, it also starred Samuel L. Jackson as Nick Fury, Chris Evans as Captain America, Chris Hemsworth as Thor, Scarlett Johansson as Black Widow and Mark Ruffalo as the Hulk. Representatives for Downey Jr did not immediately respond to a request for comment.