"Iron Metropolitan" continues in "Iron Man" #21 by Kieron Gillen, Joe Bennett and Scott Hanna, as the remnants of The Mandarin's presence in Tony Stark's futuristic city prototype begin to coalesce. Gillen's overall story starts to come together as well, although some of the weaker elements from past issues also end up getting blended in here.

Ultra-liberal journalist Abigail Burns is one of the weaker elements that Gillen improves on in this issue, including her previous one-dimensional characterization as the typical radical activist with a voice is built upon and given a little more depth. Her role as the Mandarin ring-powered Red Peril starts leaning a little more towards the heroic, providing an interesting conflict with the other characters who possess some of the other rings, and her now-softened anti-Tony Stark obsession plays well against the ever anti-Stark sentient rings of power that once belonged to The Mandarin.

Abigail as Red Peril, though, is an example of some of the issue's lingering shortcomings. Her costume as rendered by Bennett and Hanna, and colored by Guru-eFX, doesn't look all that different from that of the X-Men's Rachel Grey. Although her fire powers aren't really the same as the Phoenix, the fire that surrounds her when she uses them sure make it look that way. Maybe there are only so many ways to illustrate a redheaded female with fiery powers, and this similarity could be overlooked if there weren't other, more blatant ones. The former ruler of Mandarin city, who happens to be bald and now also powered by one of The Mandarin's rings, looks pretty similar to a familiar foe of Superman's clad in green armor. Speaking of DC, with all of these sentient rings floating around looking for new hosts, one has to wonder if Gillen thought he was writing Green Lantern for a minute.

The concept of Gillen's story; the idea of self-sustaining, high-tech cities all over the world, designed with the help of his newly-discovered step-brother; remains fascinating. Its actual execution, though, is marred by such lapses, which have plagued most of this story arc, and this particular issue also suffers from some off-sounding dialogue.

Still, Gillen adds some nice touches as well, such as Stark still being in denial regarding the recent revelation about his parents, and also a new development with his step-brother. Gillen also pays some attention to storytelling fundamentals, like reminding readers who all the players are in this issue, that make it surprisingly accessible for the fourth chapter of a five-part story. "Iron Man" #21 is a good comic that could have been better, but manages to stay enjoyable enough.