It’s Robert Downey Jr. who puts on the suit, but it’s Gwyneth Paltrow who makes “Iron Man” fly. As Pepper Potts, she is so dewy, so big-screen gorgeous, so smart, so clever … and yet vulnerable, she makes Downey’s job that much easier. All he really has to do, like everyone watching this surprisingly enjoyable first Really Big Hit of the Summer, is fall in love with her.

Not that Downey isn’t up to the other challenges of his role, like saving the world and such. The superhero in “Iron Man,” apparently originally inspired by Howard Hughes, is a brilliant inventor-entrepreneur in a jet-propelled suit of armor.

In the hands of a less gifted actor, it would just be a case of clothes make the man. But Downey makes him fascinating … and a whole lot of fun.

While not an obvious first choice to play the latest action hero in the Marvel Comics cosmos, the actor’s well-publicized personal battles with his own demons actually suit him well to play a superhero