Sadly not based on the Black Sabbath song, this big-screen version of Marvel Comics' B-list armored avenger is one of the better movies to emerge from the bloated, nerd-fed superhero genre. Billionaire weapons-maker/media playboy Tony Stark (Downey) builds an amazing suit of armor to help him escape from terrorists and decides to make a go of it as a card-carrying hero, much to the confusion of his flirty assistant (Paltrow) and chagrin of his business partner (Bridges). There's some great FX and sharp dialogue, but 95 percent of the movie's appeal comes from Downey, who brings a ridiculous charm and energy to the whole affair. On the flip side, the plot is paper-thin and you saw all the best bits in the trailer. Not exactly iron, but solid summer fun, nonetheless.