The back copy for Heaven's Door: Extra Works, the first full volume release of Keiichi Koike's work in English, calls the stories contained within “a drug in paper form.” That's not something I would know about personally, but there's no denying that there's an odd sensibility to the work so that reading them is like alternating between a dream and a nightmare in a single moment. The age rating, “suggested for mature readers,” is definitely not kidding around, but it's not necessarily maturity that you need to grasp these stories; it's a willingness to expand your reading beyond the norms of both manga and the comic format.

Of the eleven pieces in the collection, all published between 1984 and 2001, the standouts are the ones that combine the traditional and nontraditional. In part this is because such stories are a bit less work to read while still challenging the reader to think outside the panel. Lazarus Franco's 4 A.M., first published in 1985, is one of the more notable in this respect. The story has, at first glance, a fairly straightforward plot: a Japanese man visiting a friend in New York City meets a Brazilian drug dealer after a drug-fueled party. The two form an odd friendship when Lazarus insists that he's met the other man before, and they're together at a club when Lazarus is handed something called “death weed.” He explains that it is a mostly deadly drug used by an undiscovered Amazonian tribe to judge those who violate their laws. If a person is guilty, they will die after smoking it; the innocent will be safely shepherded out of the clutches of Death. Lazarus has chosen his new Japanese acquaintance to be his Shepherd, and from this point the story chronicles their experience as Lazarus is judged by Mau'na'i. (Although this sounds like an Asian Pacific language, a cursory Google search seems to indicate that it is made up by Koike.) It is nightmarish, and yet somehow exactly what Lazarus both expects and feels he deserves, and there's a sense that it is not Mau'na'i who is judging Lazarus, but Lazarus himself. The ending makes it seem that Lazarus' trial was meant to function as a warning for the other man, although whether he will choose to heed it – if he even understands it – remains an open question.

Open-ended stories are definitely a trademark of this collection, although there is some resolution to nearly all of the works. That's part of the fascination of the text, though – we can never be quite sure what it is we're meant to get out of each piece, which feels intentional. Koike's stories seem to invite us to interpret them as we will, rather than following some distinct path laid out by the creator. While Lazarus Franco's 4 A. M. is the most obvious in this respect, we can also see it clearly in Looper (1992). This piece follows a bullied elementary school boy whose mother is rarely home as he bonds with a turtle he finds by the river. The turtle, named Looper, becomes his sole friend over the course of the story, until the boy's bullies accidentally throw it out the school window. Shota, the boy in question, then has to come to terms with the loss of Looper while also trying to deal with his mother's absence and the treatment he receives at the hands of his classmates. There's a very real sense that Shota has some intellectual disabilities that his teachers do not understand (or care about), and the story comes with warnings for animal cruelty and victim-blaming – one of the most striking scenes sees Shota struggling to climb over a tall chain link fence to retrieve something the bullies have tossed there while behind him girls from school discuss how he's basically to blame for his own bullying because he's so “weird.” No one is on Shota's side except his turtle, and Looper's loss and how Shota resolves his feelings about it walk the fine line between him coming to accept his situation and learning how to best deal with the bullies. It's unsettling to say the least, all the more so because we can't necessarily pin a firm meaning on the story.

Airway, from 1996, is probably the most concrete of the tales. In this piece a man is gravely injured in a plane crash and can only be saved by receiving a transplant of brain tissue from a fellow passenger who did not survive. Although it takes a while for the plot to take shape, the way that the story unfolds – alternating between scenes of the surgery, the man on the plane, and the man's wife and child – is very well done. When the story ends we don't fully know who the man is – is he more himself, or is he more his donor? While it's odd and a bit discomfiting, it drives home the point that someone survived to come back to the wife and child, which is the most important thing. It seems to suggest that the man himself was the least important of the characters in the story, because all the doctors wanted was for him to wake up and all the wife and child wanted was a father/husband to come home. Who he is seemed almost immaterial.

Not every story in the book is a success. The four-panel Kenbo's Diary (1994) is almost too weird (and a bit gross) for it to work for all readers, and elements of The Ronin and the Sea (1985) lean too hard into slapstick, although that is perhaps the point. All of the stories have a wonderfully detailed art style that enhances the dream/nightmare qualities of the plots, and while they may be too busy for all readers, the level of tiny, intricate detail is impressive whether you love or hate it, and the oversize (like a DC or Marvel graphic novel) edition really works for the art. Heaven's Door: Extra Stories emphatically isn't going to work for everyone, but if underground comics are your thing, this is a fascinating trip into an alternative manga world.