That story involves a hundred-year war between the militaristic Fire Nation and four other, similarly element-themed “tribes”, all with their own sorcerors (“benders”) whose abilities depend on their element. The series’ main character is Aang, a young airbender who also happens to be the Avatar, the only sorceror in the world who can wield all four different kinds of magic. Over the course of the series, he assembles a team of teenagers and almost-teenagers to assist him in ending the war: waterbender Katara, who becomes his girlfriend; her brother Sokka, a non-bender who turns out to be a surprisingly effective warrior nonetheless; blind earthbender Toph; and Zuko, son of the main villain, the Firelord.
The Promise is a three-part, 210 page comic book that starts right after the series finale: The war is over and the world has been saved. With his father imprisoned, Zuko is set to become the new Firelord. The titular promise is one he begs Aang to make: if Zuko should ever be driven power-hungry and dictatorial by his new responsibilities, Aang should not hesitate to “end him” to preserve peace. Said peace is fragile, as Team Avatar (or “the Gaang”, as they are affectionately called by fans) soon discovers. Over the decades of Fire nation rule, colonies have been established in Earth Kingdom territory, and the colonists, who have lived there all their lives, are loath to leave. Zuko at first agrees to dissolve the colonies, but soon changes his mind, pitting him against the peace agreement, and against his former comrades in arms. The issue threatens to devolve into another war, and Aang is forced to consider whether to keep his promise.
Tie-in literature is often quite terrible. By its very nature, it tends to be a quick cash-in on an established property. Some franchises have better quality control for secondary material than others. The Last Airbender property is owned by Nickelodeon, who can theoretically do what they want with it. With The Promise, thankfully, they got the original creators involved, and it shows. There’s nothing cheap or inferior about it; the art, for instance, is stunningly close to the series’ animation style while still working well as motionless comic book images.
Story-wise, there is one aspect in which it actually exceeds both the original series and its sequel, The Legend of Korra: by competently tackling politics (something TLA mostly shied away from and something Korra struggled with in its first season) and managing to make it realistic and thrilling. The colonists and Zuko have a point, but so do Aang and the Earth King, and their motivations and internal struggles are believably illustrated and carry appropriate weight. The solution the Gaang eventually end up with may be a bit facile, but I never felt cheated or condescended to as a reader, so it worked for me.
As in the show, the weighty main plot is supported by mostly lighthearted sideplots. A lesser story would have tacked them on solely for comic relief purposes, and that is a purpose they do in fact serve, but they are integrated into the story both plot-wise (in that developments from the subplots eventually spill into the main plot) and thematically: For instance, Toph’s attempts to occupy a former firebender school mirror the broader struggle the Earth Kingdom citizens face in getting rid of the Fire Nation colonists; and Aang’s encounters with his Avatar fan club end up emphasising his need to come to terms with his role in the new world he helped create. That many of the plots (main and sub-) also happen to lay the groundwork for what the world looks like almost a century later, when The Legend of Korra takes place, is a neat bonus.
I’m not sure that The Promise will make a whole lot of sense to people who aren’t familiar with at least one of the franchise’s TV shows. The backstory isn’t really explained in sufficient detail. Readers who may have become interested in the world of the Avatar will likely be better served to seek out one of the two shows first. But the book likely wasn’t written with newcomers in mind: it’s a gift to the fans, a way of providing us with a new adventure without betraying the characters or falling into the typical sequel trip of creating an even bigger, more dangerous threat, and of answering some of the lingering questions left open by TLA’s series finale. It succeeds wonderfully in the first and sort of for the second. One of the more pressing questions remains unanswered for now, but that’s fine, too, since a second comic has already been announced. If it’s as good as The Promise, I’m looking forward to reading it.