Hidden Treasures is a Black Library short story by Cavan Scott. It follows two brothers that find some mysterious items in the depths of a derelict building; artefacts from a faraway war.
The two brothers Elias and Marco hide from gangs that rule the neighbourhood, but then they discover some valuable artefacts, they soon realise that they're Space Marine technology when a battered helmet of an Angel of Death, one of the Emperor's Space Marines, is found.
Marco becomes changed by the finds, whilst Elias becomes fearful. Elias realised his fears when he encounters a Space Marine while collecting artefacts on Marco's orders.
It feels like a lot gets packed into such a short story, with the way the brothers change and the realisation the situation they're in, which makes the story an enjoyable one. Focusing on brothers who have nothing to do with Space Marines or any war was interesting and the choice to briefly feature an Angel of Death was smart. It makes for a different kind of read in the Warhammer 40K world, where it is only tied into a war by the briefest of moments.
The only disappointment is that this is a short story. It is definitely one that could be made into a full novel and would be a good read showing life on a planet in the Imperium where there are just humans living out their lives. There's a lot that could be expanded on. That's what made the short story so enjoyable - it was fun to read as it was, yet leaves so many questions about what happens next in Manos City? Who were the Angels of Death fighting? Where does the Angel of Death come from? Why is there a portal in the depths of that building?