Founded in 1998, McSweeney’s Quarterley Concern began life as a magazine dedicated to publishing writing that had been rejected by other literary magazines. This rule, however, was only to last for the debut issue, and soon after McSweeney’s started featuring work that had been written specifically for its pages. Typically showcasing a mix of short stories, reportage, and illustrations, it has grown over the years to also include poetry, comic strips, and novellas.

In the run up to Halloween, the iconic American literary journal has released its 71st issue, named the Monstrous and the Terrible. Containing the publication’s first-ever deep dive into the horror genre, it also features one of its biggest lists of contributors to date. In typical McSweeney’s fashion, the contributors range from established names to budding young talent, and from the published to the unpublished.

Edited by Brian Evenson, the stories in the issue are diverse both in terms of form and subject matter. Highlights include American author Stephen Graham Jones’ alien abduction mystery; Argentine author Mariana Enríquez’s “haunting tale of childhood hijinks gone awry”, and American author Jeffrey Ford’s short story about a writer who can’t control his characters. There are also contributions from other notable authors such as Nick Antosca (who co-created the award-winning TV series the Act), Kristine Ong Muslim, Gabino Iglesias, and Natanya Ann Pulley.

In terms of its design, McSweeney’s is most notable for its ever-changing format. Previous issues have shapeshifted to become hardcovers, paperbacks, a box shaped like a human head, a bag of party balloons, a deck of playing cards, and even a pile of junk mail. Other issues have folded out into four sections and featured two spines holding the magazine together.

As you might have guessed, this latest issue is no exception. Presented as a “mind-bending, nesting-doll-like series of interlocking slipcases”, McSweeney’s writes that the design “must be seen to be believed”.

“One thing we knew from the beginning is that we wanted the packaging for this issue to be explosive,” explains artistic director Sunra Thompson. “We’re always casting around for unprecedented ways to package issues of McSweeney’s, so we spend a decent amount of time making dummies and testing stuff with printers, experimenting with packaging ideas that sometimes work and sometimes don’t. I’m sure we tend to drive printers crazy, but making dummies with printers is one of the best parts of the job.

“Anyway, the triple slipcase thing was something we’d been experimenting with for another book, and it just so happened to fit very nicely with this horror project: the nested slipcases created lots of opportunities for surprise and suspense,” he continues.

“The design of the book inside the slipcases was based on a trope that often shows up in horror stories – the ‘forbidden book’, or the ‘book of forbidden knowledge’. We wound up trying to make the book itself feel like a creepy, kinda stark old tome, with a nice leatherette casewrap, spine notches, and foil-stamped text, which hopefully contrasts well with the elaborately illustrated slipcase art.”

On the cover of the slipcases, a strange illustration of a shirtless figure shows it reaching behind to scratch its veiny, lumpy back with a long fingernail. The nightmarish drawing sets the tone for the eerie stories that readers will find inside.

“On the art side, we wanted an image that was genuinely creepy, even grotesque, but not totally off-putting – scarier than Goosebumps, more approachable than H.R. Geiger,” says Thompson. “Transformation is a theme that runs through the issue, so the basic idea was to depict something mid-transformation. We asked Jordan Speer to take on the Herculean task of creating three very elaborate images for the slipcases, of a humanlike creature transforming into something, and he wound up making something staggeringly, unimaginably cool.”

McSweeney’s 71: The Monstrous and the Terrible is out now; mcsweeneys.net