This week the CFL mailbag brought us a small white cardboard box from HarperCollins. Intriguing – firstly, because most parcels we get are book-shaped, and secondly because inside was one of those retro View-Master units – the kind that looks like futuristic binoculars, but really you insert a circular disc into it then pull the lever to see a series of slides.

The slides inside the machine seem very mysterious indeed. Maybe they hold clues about a new book, and you can help us decipher them. Although normally you’d have to hold this little red unit up to your eyes to be able to see the stereoscopic 3D images, thanks to the marvels of modern technology, we’re able to share them with you below.

The first slide is this strange shot of a My Little Pony with what looks like a bloody fingerprint on it, and some wire round its neck. Dirty and damaged toys often suggest violence towards children…

Then there’s this image of an old cigarette lighter, and more wire.

Next, an cassette tape. No iPods here, his really is a retro set of clues. The text on it is blurry in this picture, but it says Janis Joplin – a 1960s link, perhaps?

And another clue – a newspaper headline saying ‘Glowgirl caught in death’s dance’. We have no idea what these images amount to, do you?

Along with the box and the Image3D View-Master goggles, there’s a postcard of a glowing girl in a dress, and the last slide points us to the spooky book trailer you can watch below. The Shining Girls is by Lauren Beukes and is released 25 April. You can pre-order using the link at the bottom of this story.