There's plenty here to like, thanks in part to the elements already firmly established through the original film and its sequel, as well as Avengers Assemble. Downey Jr. is once again strong as Tony Stark providing a pleasing centre for everything else to orbit around. Gwyneth Paltrow returning as Pepper Potts also does well, although her relationship with Tony doesn't go anywhere new and the character doesn't get much of interest to do until towards the very end of the film. Don Cheadle is another welcome familiar face as Rhodey, although his role here never goes beyond a combination of plot device and foil-cum-sidekick to Downey Jr.'s Stark.
New additions to the cast also vary in their success. Guy Pearce crafts potentially the most successful villain of the series in Aldrich Killian, with Ben Kingsley also doing well as mysterious Osama Bin Laden-a-like The Mandarin, delivering a mid-story twist about which the less you know before watching the better. Less successful is Rebecca Hall as Dr. Maya Hansen, who is given precisely nothing interesting to do after the first ten minutes of the film; and Stephanie Szostak and James Badge Dale as two of Killian's subordinates, delivering well in the action stakes but whose villainous motivation is decidedly unclear.
Shane Black takes over directorial duties of the franchise from Jon Favreau, as well as co-writing the screenplay with Drew Pearce, and on the whole does well. This is a notably darker and more stripped down Iron Man movie to what we've seen before. We see Tony at his most vulnerable since he was imprisoned in a cave in the first installment, which provides some fresh moments of humanity for Downey Jr. to explore within the character but also makes this at times the least humorous entry into the franchise yet. Despite being roughly the same length as the previous two Iron Man films (and a good fifteen minutes shorter than Avengers Assemble) Black does feel as though he's padding things out at times here during the film's second act, especially after the film's pacy opening. The way in which Black moves the character of Tony Stark on in the film's final moments also feels a little too underdeveloped, almost like an afterthought, to resonate as much as it should.
In the end, Iron Man 3 is a mixture of successful and less successful elements, evening out into an enjoyable but flawed action film. For a third entry into the series it holds up perfectly well, certainly better than many threequels in other film series, but also feels as though it doesn't really move the franchise as a whole on to bigger and better things like it could have. Yes, there are some things that are done better here than they have been done previously, but there's also too much that feels like it's just been allowed to trundle along as it always has. Maybe it's because it's the first Marvel film to follow Joss Whedon's multi-superhero spectacular, but Iron Man 3 feels good - occasionally very good - but never great.