LOS ANGELES, Apr 24: After battling grandiose villains and teaming up with other superheroes, it’s back-to-basics for “Iron Man” in the third installment of the multi-million-dollar franchise featuring Robert Downey Jr. “Iron Man 3,” which opens in most of the world this Friday and on May 3 in the United States, has Downey reprising his role of superhero industrialist Tony Stark from the first two films as well as last summer’s “The Avengers.” (agencies)